SPREAD LOVE

Zucchini Pizza Casserole

A friendly, cozy take on pizza night that swaps a traditional crust for a tender zucchini base — light, cheesy, and loaded with classic pizza flavors. It’s a great way to use up a summer zucchini bounty or sneak extra veggies into family dinners without sacrificing that beloved melty-cheese comfort. If you enjoy crispy zucchini sides, you might also like my twist on crispy zucchini fries for an easy starter or snack.

Why make this recipe
If you’re tired of heavy, carb-laden pizza crusts and want a lighter, veggie-forward alternative, this casserole delivers the satisfaction of pizza in a more nutrient-dense package. The zucchini forms a soft, egg-and-Parmesan “crust” that holds up under a hearty meat-and-vegetable sauce, and the double layers of mozzarella and cheddar give you that ooey-gooey finish everyone loves. It’s especially useful when you want a make-ahead family meal that reheats well, stretches to feed a crowd, and sneaks in extra vegetables without drama.

Step-by-Step Guide to Making Zucchini Pizza Casserole

Ingredients

4 cups shredded zucchini
1/2 teaspoon salt
2 large eggs
1/2 cup grated Parmesan cheese
2 cups shredded mozzarella cheese, divided
1 cup shredded cheddar cheese
1 pound ground beef
1/2 cup chopped onion
2 cups pizza sauce
1 green bell pepper, chopped
1/2 cup sliced mushrooms
1/2 teaspoon dried oregano
1/2 teaspoon garlic powder
1/4 teaspoon black pepper

Directions

Prepare Zucchini
- Place 4 cups shredded zucchini in a colander and sprinkle with 1/2 teaspoon salt. Let it sit for at least 30 minutes so the salt can draw out excess water; this step is essential to prevent a watery casserole. After draining, press and squeeze the zucchini as dry as possible using a clean kitchen towel or several layers of paper towels. When it’s dry, transfer the zucchini to a bowl and mix in 2 large eggs and 1/2 cup grated Parmesan cheese until evenly combined — this mixture will act as the casserole “crust” binder.
Preheat Oven & Prepare Dish
- Preheat your oven to 375°F (190°C). Lightly grease a 9×13-inch baking dish with cooking spray or a little oil to prevent sticking and make cleanup easier.
Cook Meat & Aromatics
- Heat a large skillet over medium-high heat. Add 1 pound ground beef and brown it, breaking it into small pieces as it cooks. Once no longer pink, drain excess fat if desired. Add 1/2 cup chopped onion, the chopped green bell pepper, and 1/2 cup sliced mushrooms to the skillet. Sauté until the vegetables soften and the onion is translucent, about 5–7 minutes.
Prepare Sauce
- Stir in 2 cups pizza sauce along with 1/2 teaspoon dried oregano, 1/2 teaspoon garlic powder, and 1/4 teaspoon black pepper. Reduce heat to medium, bring the mixture to a gentle simmer, and let it cook for 5–10 minutes to allow the flavors to meld and any raw tomato taste to mellow.
Form Zucchini Base
- Press the zucchini, egg, and Parmesan mixture evenly into the bottom of the prepared 9×13-inch baking dish, smoothing it to form a compact base. Use the back of a spoon or an offset spatula to press it firmly and evenly so it holds together during baking.
Layer Casserole
- Spoon half of the meat-and-vegetable sauce evenly over the zucchini base. Sprinkle with 1 cup shredded mozzarella cheese and 1/2 cup shredded cheddar cheese. Add the remaining meat mixture in an even layer, then top with the remaining 1 cup shredded mozzarella and 1/2 cup shredded cheddar, distributing cheese to ensure a bubbly, golden top.
Bake
- Place the casserole in the preheated oven and bake for 30–35 minutes, or until the casserole bubbles around the edges and the cheese has melted and developed a light golden color. If the cheese browns too quickly, loosely tent the dish with aluminum foil to prevent over-browning while the center finishes cooking.
Rest and Serve
- Remove the casserole from the oven and allow it to rest for 10–15 minutes. This resting period is important — it lets the layers set, making cleaner slices and ensuring the zucchini base holds together when served.

Why each step matters (extra detail)

Draining the zucchini: Raw zucchini contains a surprising amount of water. Salting and pressing it removes that excess liquid, preventing the casserole from becoming soggy and ensuring the base sets correctly.
Eggs and Parmesan as binder: The eggs coagulate during baking and, together with the Parmesan, provide structure and a savory backbone to the zucchini crust.
Browning the beef and sautéing vegetables: These steps build flavor — browning develops Maillard complexity, and sautéing vegetables softens them and releases sweetness. Cooking the sauce down briefly concentrates flavors so the finished casserole isn’t watery.
Resting before slicing: Gives the casserole time to firm up so slices hold shape and presentation looks clean.

Storage Tips for Zucchini Pizza Casserole

Refrigerator: Store leftovers in an airtight container for 3–4 days at 40°F (4°C) or below.
Freezer: For longer storage, tightly wrap cooled portions or transfer to a freezer-safe container and freeze for up to 2–3 months at 0°F (-18°C). Thaw overnight in the refrigerator before reheating.
Reheating: Reheat individual slices in a 350°F (175°C) oven for 10–15 minutes or until warmed through; microwave reheating is faster (1–2 minutes) but may soften the crust more.

Serving Suggestions for Zucchini Pizza Casserole

Slice and serve hot from the oven with a crisp green salad dressed in lemon vinaigrette to cut through the richness.
Pair with roasted or steamed vegetables for a balanced plate — garlic-roasted broccoli or a simple tomato-cucumber salad complement the pizza flavors nicely.
For a lighter side, offer a bowl of fresh arugula tossed with shaved Parmesan and a drizzle of balsamic.
Make it family-style: set this casserole on the table with extra chili flakes, fresh basil, and grated Parmesan so everyone can customize their slice.

Tips to make Zucchini Pizza Casserole

Squeeze the zucchini thoroughly: Wrapping it in a towel and twisting helps remove stubborn moisture.
Don’t skip the resting period: Waiting 10–15 minutes before slicing prevents the casserole from falling apart.
Use a blend of cheeses: Combining mozzarella for stretch and cheddar for sharpness creates a more interesting flavor profile.
If you want extra crispness, broil very briefly (1–2 minutes) at the end — but watch closely to avoid burning.

Variations

Low-carb/cheddar-forward swap (bullet): Replace the pizza sauce with a sugar-free marinara and add a few tablespoons of cream cheese into the zucchini base for extra richness and a slightly tangy base. Top with extra cheddar for a sharper finish.
Vegetarian option (paragraph): Omit the ground beef and increase the mushroom and bell pepper quantities; add cooked lentils or a can of drained, rinsed chickpeas for plant-based protein. Sauté the vegetables and lentils together with a splash of soy sauce or balsamic vinegar to deepen the savory notes before stirring in the pizza sauce.

FAQs
Q: How do I prevent a watery casserole?
A: The key is salting and pressing the shredded zucchini to remove moisture, and making sure you don’t overload the zucchini base with wet ingredients. Also, simmer your meat-and-sauce mixture to evaporate excess liquid before layering.

Q: Can I use frozen zucchini?
A: Frozen zucchini often releases more water when thawed, so it’s possible to use it but you must thaw completely and press it thoroughly to remove as much moisture as possible before mixing with eggs and Parmesan.

Q: What can I substitute for ground beef?
A: Ground turkey, ground pork, or a plant-based ground meat substitute can be used. Cooking time and seasoning may need slight adjustment — add extra herbs or a splash of soy sauce if the flavor is mild.

Q: Can I make this ahead of time?
A: Yes. Assemble the casserole and refrigerate (covered) for up to 24 hours before baking. If baking from chilled, you may need to add 5–10 minutes to the bake time.

Q: Is this recipe gluten-free?
A: Yes — as written, this casserole is naturally gluten-free provided your pizza sauce and any processed cheeses are labeled gluten-free. If anyone has strict dietary needs, check labels on packaged ingredients.

Troubleshooting and pro tips

If your base is falling apart after baking: You may need to remove more moisture from the shredded zucchini next time or increase the egg/parmesan ratio slightly to help bind it more firmly.
If the top browns too fast: Tent loosely with foil during baking, removing the foil for the last 5–7 minutes to encourage browning if desired.
Want more flavor depth: Stir a teaspoon of tomato paste into the meat sauce while sautéing the vegetables, then allow it to caramelize briefly before adding the pizza sauce.

Scaling, make-ahead, and serving for crowds

To feed a crowd, double the recipe and use a larger roasting pan or two 9×13 dishes. Baking time may increase slightly; check for bubbling edges and golden cheese.
This casserole is excellent for potlucks since it travels well and can be served at room temperature. Keep warm in an oven set to a low temperature (200°F / 95°C) if needed.
For meal prep, divide into single-serving containers and refrigerate. Reheat in the oven or microwave for quick lunches or dinners.

Nutrition and health notes

Swapping a traditional crust for zucchini reduces net carbs and increases vegetable intake. The zucchini contributes fiber and vitamins while cheeses provide protein and fat for satiety.
To reduce calories, use lean ground beef or ground turkey and choose reduced-fat cheeses, though flavor and texture will change a bit. Adding more vegetables (spinach, zucchini, peppers) can bulk up volume without many extra calories.

A final word on texture and flavor
This casserole balances soft, tender zucchini base with robust, savory meat sauce and layers of melted cheese. The Parmesan in the zucchini mixture gives a salty, nutty undertone that helps the base behave more like a traditional crust in mouthfeel. The layered assembly not only distributes flavor evenly but also allows the top to get golden and slightly crispy while the middle remains moist and satisfying.

Conclusion

If you want an alternate take on pizza that’s lighter and vegetable-forward, the recipe from Zucchini Pizza Casserole | Low-Carb & Gluten-Free offers a low-carb perspective worth exploring. For another tested home-cook version with tips, see the detailed write-up at Zucchini Pizza Casserole Recipe: How to Make It – Taste of Home.