This zucchini pizza casserole has become my go-to for busy weeknights when everyone wants pizza but I want something a little lighter and packed with vegetables. I first put this together on a rainy evening when the kids were begging for slices and my refrigerator was generous with zucchini. The shredded zucchini forms a surprisingly sturdy crust once drained and baked; it’s tender at the center with a lightly browned edge that holds the savory beef-and-pepper topping. The balance of melty mozzarella and sharp cheddar on top gives it that indulgent pizza finish without needing dough.

I discovered this combination while experimenting with ways to use an abundant summer harvest. The first batch was a lovely surprise: the crust stayed intact after slicing, the sauce seeped into the zucchini just enough for cohesion, and the family declared it “better than takeout.” Texture is key here — properly squeezing the zucchini keeps the crust from becoming watery, and pre-baking the base gives you a concentrated zucchini flavor rather than a steamed one. Serve with a crisp green salad and you have a complete meal that feels celebratory yet simple enough for any night.

Ingredients

• Shredded zucchini (4 cups): Choose medium to large zucchini; shred with a box grater or food processor. Draining is essential to avoid a soggy base and concentrates the mild squash flavor.
• Salt (1/2 teaspoon): Draws out moisture from zucchini; use kosher or sea salt for best control and flavor.
• Large eggs (2): Act as the binder that holds the zucchini crust together — room temperature eggs mix more evenly.
• Grated Parmesan (1/2 cup): Adds umami and helps dry the crust slightly; freshly grated Parm grates and melts better than pre-shredded.
• Mozzarella, shredded (2 cups, divided): Use low-moisture whole-milk mozzarella for melty pull; reserve half for the crust and the rest for topping.
• Cheddar, shredded (1 cup): Adds sharpness on top for a contrast to the mozzarella’s creaminess; extra cheddar gives a nice golden finish.
• Ground beef (1 pound): Choose 80/20 for flavor or 90/10 to reduce fat; brown and drain before adding to the sauce.
• Onion, chopped (1/2 cup): Yellow or sweet onion brings sweetness and depth when softened with the beef.
• Pizza sauce (2 cups): Use a good-quality jarred sauce or homemade marinara; it’s the flavor backbone, so a robust, herby sauce is best.
• Green bell pepper (1, chopped): Adds freshness and crunch; sauté until slightly softened so it stays bright.
• Mushrooms (1/2 cup, sliced): Optional but recommended — they add earthiness and absorb the sauce flavor.
• Dried oregano (1/2 teaspoon) & garlic powder (1/2 teaspoon): Classic pizza seasonings; they marry the topping components to the crust.
• Black pepper (1/4 teaspoon): Freshly ground for the best aroma.

Instructions

Preheat and prep: Preheat your oven to 4006F. Grease a 9x13-inch baking dish with a little oil or nonstick spray so the zucchini crust releases easily after baking. This temperature ensures the crust sets quickly without overcooking the topping later. Salt and drain the zucchini: Place 4 cups shredded zucchini in a large bowl and sprinkle with 1/2 teaspoon salt. Let sit for 10 minutes to draw out moisture. After resting, transfer zucchini to a clean kitchen towel or cheesecloth and squeeze firmly until nearly all liquid is expelled. Removing water is crucial to prevent a watery final dish. Make the crust mixture: Return the drained zucchini to the bowl and add 2 large eggs, 1/2 cup grated Parmesan, and 1 cup (half) shredded mozzarella. Mix thoroughly so the eggs coat the zucchini and the cheeses start to bind — this combination clumps together well and bakes into a cohesive layer. Form and bake the crust: Press the zucchini mixture evenly into the prepared 9x13-inch dish, packing it down to create a uniform thickness. Bake for 20 minutes, until set and lightly browned around the edges. A fork inserted into the center should come out mostly clean and the top will be slightly firm to the touch. Brown the beef and build the topping: While the crust bakes, brown 1 pound ground beef with 1/2 cup chopped onion in a skillet over medium heat until no pink remains. Drain excess fat, then stir in 2 cups pizza sauce, 1 chopped green bell pepper, 1/2 cup sliced mushrooms, 1/2 teaspoon dried oregano, 1/2 teaspoon garlic powder, and 1/4 teaspoon black pepper. Simmer for about 5 minutes so the flavors meld and the vegetables soften but retain some texture. Assemble and finish baking: Spread the meat mixture evenly over the pre-baked zucchini base. Sprinkle the remaining 1 cup mozzarella and all of the 1 cup shredded cheddar on top. Return to the oven and bake an additional 20 minutes, until the cheese is fully melted, bubbling, and golden in spots. Let rest for 5 minutes before slicing so the layers set.

Storage Tips

Cool the casserole to room temperature before storing. For refrigeration, transfer leftovers to an airtight container and eat within 3 to 4 days. To freeze, slice into portions, wrap each piece tightly in plastic wrap, then place in a freezer-safe bag or container for up to 3 months. Reheat from frozen in a 3506F oven for 2005 minutes covered with foil, then remove the foil for 5 minutes to refresh the crust. In the microwave, reheat individual portions on medium power to avoid rubbery cheese.

Ingredient Substitutions

If you prefer leaner meat, swap ground turkey or chicken for the beef; add a tablespoon of olive oil when browning to preserve flavor. For a vegetarian version, replace meat with cooked lentils or a plant-based ground substitute and increase the seasoning to compensate. If you want a crisper base, stir in 1/4 cup almond flour or crushed pork rinds as a binder (not gluten-free if using pork rinds). Swap mozzarella for provolone or fontina for a different melt profile, and use a low-sodium pizza sauce to control salt.

Serving Suggestions

Serve slices with a peppery arugula salad dressed in lemon vinaigrette, garlic-parmesan roasted potatoes, or a simple tomato-cucumber salad. Garnish with torn fresh basil or chopped parsley and a drizzle of good olive oil. For a party, cut into squares and serve as finger food with toothpicks; offer hot pepper flakes and grated Parmesan for guests to customize their pieces.

Cultural Background

This dish is a contemporary American twist on classic pizza, inspired by low-carb and vegetable-forward adaptations that gained popularity in home cooking. The idea of using vegetables as crusts or bases — cauliflower, eggplant, and zucchini among them — reflects a larger trend toward incorporating produce into traditional comfort foods without losing the original flavors. While not rooted in a regional cuisine, the combination of oregano, garlic, tomato sauce, and melted cheeses keeps the flavor profile unmistakably pizza-like, bridging Italian-American tradition with modern home-cooking creativity.

Seasonal Adaptations

In summer, use fresh, high-quality pizza sauce or quick-roasted tomatoes for brighter flavor and peak zucchini. In cooler months, add roasted root vegetables or swap bell pepper for caramelized onions and roasted mushrooms for a heartier feel. For holiday dinners, top with shredded smoked mozzarella and chopped roasted garlic for a more robust, festive version that still highlights the vegetable base.

Meal Prep Tips

Make the crust and meat topping separately ahead of time. Store the baked crust and cooled meat mixture in separate airtight containers in the refrigerator for up to 2 days, then assemble and bake when ready. This two-step prep shortens active time on the day you serve and helps maintain texture — reheating a pre-baked crust briefly in the oven before adding the topping refreshes it nicely.

Give this casserole a try on your next pizza night. It’s an elegant, practical way to enjoy familiar flavors with extra vegetables, and once you master the draining and pre-bake, it becomes reliably delicious every time. Share a slice, and you might just convert another pizza purist.