Cheesy Zucchini Casserole: A Garden-Fresh Comfort Classic

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This golden-topped Cheesy Zucchini Casserole transforms humble garden zucchini into an irresistible side dish with its perfect balance of fresh vegetable flavor and indulgent creaminess. The dish showcases tender slices of zucchini layered to create a beautiful pattern, all enveloped in a rich, herb-infused cheese sauce and topped with a crispy, golden breadcrumb crust. Every bite delivers an exquisite combination of textures—from the tender yet firm zucchini to the molten, stretchy cheese and the satisfying crunch of the toasted breadcrumb topping. This elegant casserole exemplifies sophisticated comfort food at its finest—ideal for holiday gatherings, summer potlucks, or whenever you need a delicious way to showcase abundant garden zucchini without overwhelming preparation.

Why You’ll Love This Recipe

• Garden vegetable showcase: Highlights fresh zucchini in its prime with minimal processing
• Make-ahead convenience: Can be assembled hours before baking
• Crowd-pleaser: Appeals to vegetable skeptics with its cheesy goodness
• Visually impressive: Creates beautiful presentation with minimal fuss
• Versatile occasions: Perfect for summer gatherings, holiday sides, and weeknight dinners
• Textural delight: Offers tender, creamy, and crispy elements in each bite
• Simple technique: Requires basic culinary skills with impressive results
• Customizable: Easily adapts to different cheeses and herb profiles
• Complete presentation: Works as both side dish and vegetarian main course
• Budget-friendly: Makes the most of seasonal abundance and pantry staples

Ingredients

For the Zucchini Base

• Fresh zucchini – Provides the foundation with sweet, mild flavor and beautiful texture
• Yellow squash (optional) – Adds color contrast and complementary flavor
• Salt – Draws out excess moisture and seasons the vegetables
• Olive oil – Enhances flavor and helps prevent sticking during layering
• Fresh herbs – Provides aromatic depth and visual appeal

For the Cheese Sauce

• Butter – Creates rich base for sauce and adds golden flavor
• All-purpose flour – Thickens sauce for perfect consistency
• Milk – Forms creamy base with balanced richness
• Heavy cream – Adds luxurious mouthfeel and prevents curdling
• Garlic – Contributes aromatic depth and savory notes
• Onion powder – Adds subtle sweetness and complexity
• Multiple cheeses – Creates depth of flavor and perfect melt factor
• Dijon mustard – Enhances cheese flavor with gentle tang
• Nutmeg – Adds traditional warm note to complement cheese sauce
• White pepper – Seasons without visual disruption to the sauce

For the Crunchy Topping

• Panko breadcrumbs – Provides superior crunch and golden appearance
• Grated Parmesan – Adds savory depth and helps with browning
• Butter – Ensures crisp texture and rich flavor
• Fresh parsley – Adds color contrast and fresh flavor note
• Paprika – Contributes subtle warmth and attractive color

Optional Enhancements

• Diced red bell pepper – Adds vibrant color and sweet contrast
• Fresh herbs – Enhances with thyme, basil, or dill notes
• Caramelized onions – Provides sweet depth and additional texture
• Pine nuts – Adds buttery nutty flavor and textural interest
• Cherry tomatoes – Creates bright acidity and visual appeal
• Crispy bacon crumbles – Introduces smoky flavor and savory boost
• Leeks – Offers delicate onion flavor for added complexity
• Summer corn kernels – Adds sweet pops of texture and summer flavor
• Italian seasoning – Creates Mediterranean flavor profile
• Crushed red pepper flakes – Adds gentle heat for contrast

Step-by-Step Instructions

Preparing the Zucchini

Begin by preheating your oven to 375°F (190°C), ensuring it reaches the proper temperature for even browning of the breadcrumb topping and perfect melting of the cheese sauce.

Wash 4-5 medium zucchini thoroughly and pat dry with paper towels. For best presentation and even cooking, trim the ends and slice into uniform ¼-inch thick rounds. If using both green zucchini and yellow squash, the color contrast will create a more attractive finished dish.

Place the sliced zucchini in a colander set over a bowl and sprinkle with 1 teaspoon of salt, tossing gently to distribute. Allow the zucchini to sit for 15-20 minutes to draw out excess moisture, which prevents a watery casserole and concentrates the flavor. This step is crucial for achieving the perfect texture in the final dish.

While the zucchini releases moisture, lightly butter a 9×13-inch baking dish or an 11-inch oval gratin dish, ensuring complete coverage to prevent sticking and ease serving later. The butter also adds a subtle richness to the edges of the casserole where it makes contact with the dish.

After the resting period, gently pat the zucchini dry with paper towels or a clean kitchen towel. Removing excess moisture is essential for a casserole with well-defined texture rather than a soggy result.

In a small bowl, combine 2 tablespoons of olive oil with 1 teaspoon of minced garlic, ½ teaspoon dried thyme (or 1 teaspoon fresh), and a pinch of black pepper. This seasoned oil will add flavor to the zucchini before it’s layered in the dish.

Gently toss the dried zucchini slices in the seasoned olive oil mixture until evenly coated. This light coating ensures the zucchini develops flavor even before the cheese sauce is added, creating depth in the final dish.

Creating the Cheese Sauce

In a medium saucepan, melt 3 tablespoons of butter over medium heat until foaming subsides. Watch carefully to prevent browning, as you want the sauce to maintain its creamy white appearance.

Add 3 tablespoons of all-purpose flour to the melted butter, whisking constantly to form a smooth paste (roux). Continue cooking and whisking for 1-2 minutes to cook out the raw flour taste while maintaining a pale color. This brief cooking creates a roux that will thicken the sauce without adding color or nutty flavor.

Gradually add 1½ cups of warm milk and ½ cup of heavy cream to the roux, whisking continuously to prevent lumps from forming. The warm dairy incorporates more smoothly than cold, resulting in a silkier sauce.

Bring the mixture to a gentle simmer over medium heat, stirring constantly with a wooden spoon or heat-resistant spatula. As the sauce heats, it will begin to thicken enough to coat the back of a spoon, typically taking 3-5 minutes.

Once the sauce has thickened, reduce heat to low and add 2 cups of shredded cheese, incorporating ½ cup at a time and stirring until completely melted before adding more. A combination of cheeses creates the most complex flavor—consider 1 cup of sharp cheddar for flavor, ½ cup of mozzarella for stretch, and ½ cup of Gruyère for nutty depth.

Season the cheese sauce with ½ teaspoon of salt, ¼ teaspoon of onion powder, a pinch of white pepper, a pinch of nutmeg, and ½ teaspoon of Dijon mustard. The mustard enhances the cheese flavor without adding a pronounced taste of its own.

Continue stirring over low heat until the sauce is completely smooth and has reached a consistency that will coat the zucchini without being too thick or too runny. The perfect sauce should slowly flow off the spoon rather than clumping or running like water.

Remove from heat and set aside while you prepare the breadcrumb topping. The residual heat will keep the sauce pliable for assembly without continuing to thicken it excessively.

Preparing the Breadcrumb Topping

In a small skillet, melt 2 tablespoons of butter over medium heat until just melted. The butter will coat the breadcrumbs for even browning and add richness to the topping.

Add 1 cup of panko breadcrumbs to the melted butter, stirring constantly until the crumbs are evenly coated but not browned. The breadcrumbs will brown during baking, so you’re only preparing them for that process at this stage.

Remove the skillet from heat and stir in ¼ cup of freshly grated Parmesan cheese, 2 tablespoons of finely chopped fresh parsley, and ¼ teaspoon of paprika. This mixture creates a topping with color, flavor, and the perfect texture contrast to the creamy casserole beneath.

Set the breadcrumb mixture aside while you assemble the casserole. The cooling period allows the butter to slightly set around the crumbs, which helps them maintain distinct texture rather than clumping together.

Assembling and Baking the Casserole

Pour a thin layer (approximately ¼ cup) of the cheese sauce into the bottom of the prepared baking dish, spreading it evenly to create a base that prevents sticking and starts the layering process with flavor.

Arrange half of the zucchini slices in the baking dish, slightly overlapping them in an attractive pattern. For the most appealing presentation, alternate green zucchini and yellow squash if using both, or arrange the slices in concentric circles or neat rows.

Pour half of the remaining cheese sauce over the first layer of zucchini, using a spatula to ensure even coverage while allowing some of the zucchini pattern to remain visible. This creates both visual interest and ensures proper cheese distribution throughout the dish.

Create a second layer with the remaining zucchini slices, arranging them in the same pattern but offset from the first layer for the most stable structure and attractive appearance when served.

Pour the remaining cheese sauce over the top layer of zucchini, ensuring all pieces are covered but not completely submerged. The zucchini should be visible through the sauce for the most attractive presentation.

Sprinkle the prepared breadcrumb mixture evenly over the top of the casserole, covering the entire surface with a consistent layer. Avoid pressing the crumbs into the cheese sauce, as this will prevent them from developing their characteristic crunch during baking.

Place the assembled casserole on a baking sheet to catch any potential overflow and make handling easier. This precaution protects your oven from spills and makes transferring the hot dish safer.

Bake in the preheated oven for 25-30 minutes until the top is golden brown and crispy, and the cheese sauce is bubbling around the edges. If the top browns too quickly, tent loosely with aluminum foil to prevent burning while allowing the casserole to finish cooking.

For an extra-golden top, place under the broiler for the final 1-2 minutes, watching constantly to prevent burning. This step creates an irresistible textural contrast between the crispy top and the creamy interior.

Once baked, allow the casserole to rest for 5-10 minutes before serving. This brief resting period allows the cheese sauce to set slightly, making for neater portions when cutting and serving.

Final Presentation and Serving

Remove the baked casserole from the oven and place on a heat-safe surface or trivet. The dish will be extremely hot and needs a proper resting place to prevent damage to countertops.

If desired, garnish the casserole with additional fresh herbs such as chopped parsley, basil, or chives just before serving. This adds a fresh color contrast to the golden top and provides a burst of aromatics when the dish is brought to the table.

For the most impressive presentation, serve the casserole in its baking dish at the table, scooping portions with a wide serving spoon to showcase the beautiful layers and stretchy cheese.

Alternatively, pre-portion the casserole into neat squares or rectangles for a more formal plated presentation, garnishing each serving individually with a small herb sprig or light dusting of paprika.

Serve hot as a substantial side dish alongside grilled meats or roast chicken, or present as a vegetarian main course accompanied by a crisp green salad and crusty bread to complete the meal.

For casual gatherings, place the casserole on a trivet in the center of the table family-style, allowing guests to help themselves to this visually impressive yet comforting dish.

Pro Tips

• Salt and drain zucchini thoroughly to prevent a watery casserole
• Use a mandoline for consistently thin, even zucchini slices
• Pat zucchini completely dry after salting for best texture
• Layer cheeses for complex flavor and optimal melting properties
• Warm milk before adding to roux for smoother sauce with fewer lumps
• Don’t skimp on the breadcrumb layer—it provides essential texture contrast
• Allow the casserole to rest before serving for cleaner portions
• Use freshly grated cheese rather than pre-shredded for better melting
• Add cheese to the sauce gradually for the smoothest incorporation
• Season each component separately for balanced flavor throughout
• Consider slicing some zucchini lengthwise for visual variety
• Serve with a simple acidic element like lemon wedges to balance richness
• For deeper flavor, briefly sauté zucchini before assembling
• Position oven rack in upper-middle position for optimal browning
• Test zucchini doneness by inserting a knife—it should meet little resistance
• For extra flavor depth, add a splash of white wine to the cheese sauce
• Let the casserole sit 10 minutes before serving to set up properly
• Use a combination of cheddar and mozzarella for flavor and stretch
• Add a pinch of dried herbs to the breadcrumb mixture for aroma
• For elegant service, bake in individual gratin dishes for 20-25 minutes

Variations and Creative Ideas

Cheese Variations

Mediterranean Zucchini Gratin: Replace standard cheeses with a combination of feta, halloumi, and a touch of Parmesan, then add olives, sun-dried tomatoes, and oregano for a Greek-inspired variation.

Blue Cheese and Walnut Zucchini Casserole: Incorporate crumbled blue cheese into the sauce and add toasted walnuts to the breadcrumb topping for a sophisticated flavor profile with interesting textural elements.

Goat Cheese and Herb Zucchini Tian: Layer zucchini with dollops of soft goat cheese and fresh herbs between each layer instead of a traditional cheese sauce for a lighter, tangy alternative with bright herbaceous notes.

Smoked Gouda Zucchini Casserole: Use smoked Gouda as the primary cheese for a robust, smoky flavor that complements the mild zucchini perfectly, adding depth without overwhelming the fresh vegetable.

Regional Adaptations

Italian-Style Zucchini Parmesan: Layer the zucchini with Italian seasonings, fresh mozzarella, and a light tomato sauce, finishing with Parmesan and breadcrumbs for a vegetable take on the classic eggplant dish.

Greek Zucchini Casserole: Incorporate lemon zest, dill, and feta cheese into the layers, topping with a mixture of breadcrumbs and crushed phyllo for a Mediterranean-inspired dish with bright flavors.

Southern Squash Casserole Twist: Add sautéed onions, pimientos, and a touch of cayenne to the cheese sauce, topping with crushed butter crackers mixed with Parmesan for a Southern-inspired comfort food classic.

French Provençal Zucchini Gratin: Layer with herbes de Provence, caramelized onions, and Gruyère cheese, adding a touch of white wine to the sauce for an elegant French countryside interpretation.

Dietary Adaptations

Gluten-Free Version: Substitute the flour in the cheese sauce with cornstarch or gluten-free flour blend, and use gluten-free breadcrumbs or crushed gluten-free crackers for the topping.

Lower-Carb Option: Replace the breadcrumb topping with a mixture of almond flour, grated Parmesan, and herbs for a crunchy finish with fewer carbohydrates and added protein.

Dairy-Free Adaptation: Create a creamy sauce using cashew cream, nutritional yeast, and dairy-free cheese alternatives, with a topping of seasoned nutritional yeast and gluten-free breadcrumbs.

Vegan Variation: Combine silken tofu, nutritional yeast, and plant-based milk for the sauce base, using vegan cheese shreds and adding turmeric for color, topped with seasoned panko and olive oil.

Seasonal Specialties

Summer Garden Zucchini Casserole: Incorporate fresh corn kernels, cherry tomatoes, and basil between the zucchini layers for a celebration of peak summer produce in one colorful dish.

Fall Harvest Zucchini Bake: Add thin apple slices, sage, and a touch of maple syrup to the cheese sauce for a sweet-savory autumnal variation perfect for holiday tables.

Spring Vegetable Medley Casserole: Combine zucchini with asparagus pieces and fresh peas, using a lighter cheese sauce flavored with lemon and mint for a refreshing spring option.

Winter Comfort Zucchini Gratin: Layer with caramelized onions, thinly sliced potatoes, and hearty Gruyère cheese with a hint of nutmeg for a substantial cold-weather version.

Storage and Make-Ahead Advice

Short-Term Storage:

• Store baked casserole covered in the refrigerator for up to 3 days.
• Wrap tightly with aluminum foil or transfer to airtight containers to maintain freshness and prevent absorption of other food odors.
• For best texture, portion leftovers before storing to minimize repeated reheating of the entire dish.
• If storing unbaked assembled casserole, keep refrigerated for no more than 24 hours before baking to prevent the zucchini from releasing too much liquid.
• Consider underbaking the casserole slightly if you know you’ll be reheating portions later, as this prevents overcooking during the reheating process.

Reheating Guidelines:

• Reheat individual portions in the microwave at 70% power for 2-3 minutes until heated through but not overcooked.
• For whole leftover casserole, cover with foil and reheat in a 325°F (165°C) oven for 15-20 minutes until hot throughout.
• To restore crispness to the breadcrumb topping, finish reheating uncovered for the final 5 minutes or place under the broiler briefly.
• Add a sprinkle of fresh breadcrumb and cheese mixture before reheating to refresh the topping if it has softened during storage.
• For best texture, allow refrigerated casserole to come to room temperature for 15-20 minutes before reheating.

Make-Ahead Strategy:

• This casserole can be partially prepared ahead of time for convenience without sacrificing quality.
• Prepare the zucchini (slice, salt, and drain) up to 24 hours in advance, storing in a covered container in the refrigerator.
• Make the cheese sauce up to 2 days ahead and store in an airtight container in the refrigerator, rewarming gently on the stovetop and whisking before assembly.
• Prepare the breadcrumb topping mixture (without melting the butter) and store in an airtight container at room temperature for up to 3 days, then combine with melted butter just before topping the casserole.
• For day-of ease, assemble the entire casserole up to 4 hours before baking, cover, and refrigerate, then bring to room temperature for 30 minutes before baking as directed.
• If making for a potluck or transport, consider slightly underbaking at home, then finishing at the destination for the freshest texture and presentation.

Freezing Guidelines:

• While zucchini casseroles can be frozen, the texture of the zucchini may become softer upon thawing and reheating.
• For best results if freezing, slightly undercook the zucchini during the initial baking and cool completely before wrapping.
• Freeze in portion-sized containers for up to 2 months for easier reheating without thawing the entire casserole.
• Thaw frozen casserole overnight in the refrigerator before reheating for the best texture results.
• Consider adding a fresh breadcrumb topping after thawing but before reheating to restore the crispy texture.
• When preparing specifically for freezing, reduce the amount of cheese sauce slightly to account for additional moisture released during freezing and thawing.

Party Prep Tips:

• For entertaining, prepare multiple smaller casseroles rather than one large one for more even cooking and elegant presentation.
• Create a breadcrumb bar with various toppings (plain, herb, parmesan, spicy) in separate ramekins for guests to customize their portions.
• For buffet service, bake in a wider, shallower dish to create more surface area for the crispy topping and easier serving.
• Prepare decorative vegetable curls or herb bouquets in advance for quick final garnishing that elevates presentation.
• Double the breadcrumb topping recipe and serve the extra on the side for guests who enjoy additional crunch.
• Create a timeline working backward from serving time, allowing for vegetable draining time, sauce preparation, assembly, and baking with a 10-minute rest period.

Entertainment Value and Presentation

This elegant casserole offers many opportunities to enhance your dining presentation:

Serving Suggestions: Present in a beautiful ceramic gratin dish with a wide serving spoon to showcase the layers.

Visual Enhancements: Create attractive patterns with the zucchini slices, such as concentric circles or herringbone arrangements.

Garnish Options: Arrange thin lemon wheels, fresh herb sprigs, and edible flowers around the serving platter.

Individual Portions: For elegant service, bake in individual gratin dishes or ramekins for personal servings with maximum crispy topping.

Menu Pairings: Accompany with roasted chicken, grilled salmon, or as part of a vegetarian spread with crusty bread and roasted tomatoes.

Theme Development: Create seasonal variations with coordinating side dishes that highlight complementary produce.

Timing Perfection: Choreograph preparation to serve the casserole directly from oven to table with a dramatic garnishing moment.

Presentation Ware: Serve in a colorful enameled cast iron dish that holds heat beautifully for extended service.

Color Enhancement: Add bright garnishes like quick-pickled red onion or fresh cherry tomatoes for vibrant presentation.

Interactive Elements: Provide small dishes of additional toppings like toasted nuts, crispy fried herbs, or chili oil for personalization.

Frequently Asked Questions

Why is my zucchini casserole watery? Excessive moisture is the most common issue with zucchini casseroles and typically results from insufficient pre-treatment of the zucchini. These vegetables naturally contain over 90% water, which releases during cooking. To prevent a watery result, be thorough with the salting and draining process—ensure you salt the sliced zucchini and allow at least 15-20 minutes for moisture extraction, then pat thoroughly dry with paper towels or a clean kitchen towel. For extra insurance, you can place the salted zucchini between layers of paper towels with a weight on top to press out additional moisture. Another preventive measure is ensuring your cheese sauce is properly thickened with enough roux (butter and flour mixture), as this helps absorb any residual moisture released during baking. Finally, avoid covering the casserole during baking unless specified, as this traps steam and increases moisture in the dish.

Can I use yellow summer squash instead of zucchini? Yes, yellow summer squash makes an excellent substitute or complement to zucchini in this casserole, with nearly identical cooking properties and moisture content. The main difference is purely aesthetic—the bright yellow color creates beautiful contrast, especially when alternated with green zucchini in the layering. Yellow squash tends to have a slightly sweeter flavor profile that pairs wonderfully with the cheese sauce. When using yellow squash, follow the exact same preparation method as for zucchini, including the crucial salting and draining step. For the most attractive presentation, consider using both vegetables in the same casserole, creating alternating layers or patterns that add visual interest to the finished dish. The cooking time remains the same regardless of which squash variety you choose.

How do I know when the casserole is properly cooked? A perfectly cooked zucchini casserole strikes the balance between tender vegetables and a crispy top while avoiding mushiness. Visually, look for a golden brown, crispy breadcrumb topping and bubbling cheese sauce around the edges of the dish. Insert a small knife into the center of the casserole—it should slide through the zucchini with slight resistance; completely soft zucchini indicates overcooking. The internal temperature should reach approximately 160°F (71°C) in the center. Another indicator is the thickened state of the cheese sauce—it should no longer appear watery or separated. Finally, the casserole should have a settled appearance rather than a soupy texture, with distinct vegetable layers visible when you serve it. If the top is browning too quickly but the center still seems undercooked, cover loosely with foil for the remaining baking time.

What cheese combinations work best for the sauce? The ideal cheese combination balances flavor, meltability, and texture for the perfect sauce. Sharp cheddar provides robust flavor and good color, while mozzarella or fontina offers exceptional stretchiness for that appealing cheese-pull effect. Gruyère or Swiss adds nutty complexity and melts beautifully, while Parmesan contributes savory depth and helps thicken the sauce. For optimal results, use a base ratio of 50% good melting cheese (mozzarella, fontina, or Monterey Jack), 25% flavorful aged cheese (sharp cheddar, Gruyère, or provolone), and 25% flavor-enhancing hard cheese (Parmesan, Pecorino, or Asiago). Always grate cheese fresh rather than using pre-shredded varieties, which contain anti-caking agents that can make sauces grainy. For specialized versions, consider goat cheese for tanginess, smoked gouda for depth, or blue cheese (used sparingly) for bold character. Regardless of type, add cheese to the sauce gradually off the heat, allowing each addition to melt completely before adding more.

Can I make this casserole without breadcrumbs for a low-carb option? Yes, several delicious alternatives create a satisfying crunchy topping without traditional breadcrumbs. The most popular low-carb substitute is a mixture of grated Parmesan cheese, almond flour, and crushed pork rinds, which creates an exceptionally crispy golden top when mixed with melted butter. Another excellent option combines crushed raw pecans or walnuts with Parmesan cheese and herbs. For a simple approach, use just Parmesan and herbs, which will form a crispy cheese crust during baking. Nutritional yeast flakes mixed with a small amount of almond flour provide a cheesy, crispy topping with minimal carbs. Regardless of which alternative you choose, the key is including some fat (usually melted butter or olive oil) to help the topping brown properly and adhere to the casserole. The baking time remains the same, though you may want to watch the topping carefully as nut-based alternatives can brown more quickly than traditional breadcrumbs.

How can I add protein to make this a complete meal? Transforming this zucchini casserole into a protein-rich complete meal is simple with strategic additions. For meat options, consider layering 2 cups of shredded rotisserie chicken, 1 pound of browned ground turkey seasoned with Italian herbs, or 8 ounces of diced ham between the zucchini layers before adding the cheese sauce. Seafood variations work beautifully too—fold 8 ounces of lump crab meat or 10 ounces of small cooked shrimp into the cheese sauce before assembling. For vegetarian protein, add 1½ cups of cooked quinoa, 2 cups of drained and rinsed white beans, or 8 ounces of crumbled firm tofu sautéed with garlic and herbs between layers. Another excellent approach is adding a protein-rich cheese layer using 2 cups of ricotta mixed with an egg and herbs, spread between zucchini layers. When adding protein components, ensure they’re pre-cooked and well-seasoned, as they won’t cook substantially during the casserole’s baking time. Also, slightly increase the cheese sauce volume by about 25% to accommodate the additional ingredients while maintaining the dish’s creamy texture.

What’s the best way to serve this for a larger crowd? For serving 12 or more people, strategic scaling and preparation adjustments can maintain quality while increasing quantity. Instead of simply doubling the recipe in one large, deep dish (which can lead to uneven cooking), prepare two standard-sized casseroles in parallel. This approach ensures proper cooking throughout and provides flexibility in presentation and serving. For buffet service, consider preparing in disposable aluminum pans with slightly reduced depth for more consistent cooking and easier transport. Pre-cut into squares before presenting on the buffet to facilitate easy serving. If making significantly ahead of time, slightly underbake, then finish heating just before serving to maintain optimal texture. Create visual variety by preparing one traditional version and one with a variation—perhaps adding cherry tomatoes or different herbs—which accommodates more preferences while providing visual interest on the buffet table. For portion planning, a standard 9×13-inch casserole typically serves 8-10 as a side dish; when serving as a main course, plan for 6-8 portions per casserole. Always prepare about 20% more than your exact headcount to accommodate second helpings of this popular dish.