This Cheesy Pizza Zucchini Bake is a high-protein, low-carb dinner made with roasted zucchini, seasoned ground beef, thick tomato sauce, mozzarella, Parmesan, and your favorite pizza toppings. The zucchini is sliced into planks and roasted before layering, which helps prevent the watery base that can happen with zucchini casseroles.

If you love pizza but don’t need the crust, this is an easy way to get all those familiar pizza flavors in a hearty, cheesy casserole.

It’s family-friendly, naturally gluten-free, high in protein, and easy to customize with your favorite pizza toppings.

Why You’ll Love This Zucchini Pizza Bake

• No soggy zucchini base: Roast the zucchini first to drive off excess moisture.
• High in protein: Ground beef and plenty of cheese make this a satisfying dinner.
• No complicated sauce: Simmer passata directly with the beef until thick.
• Easy ingredients: No specialty low-carb products or expensive ingredients are needed.
• Pizza night flavors: Mozzarella, Parmesan, pepperoni, bell pepper, olives, and Italian seasoning bring all the pizza flavor.
• Great for meal prep: The casserole slices even more neatly once chilled.

What Makes This Zucchini Pizza Bake Different?

Many zucchini pizza casseroles use shredded zucchini to create a crust. This recipe takes a different approach: zucchini is sliced into thick planks, roasted, and layered like lasagna.

The zucchini stays recognizable instead of disappearing into the casserole, while the layers give you a hearty, satisfying texture.

The other important step is the meat sauce. Rather than adding thin passata directly to the casserole, simmer the passata uncovered with the beef until thick. Together, the roasted zucchini and reduced meat sauce help keep excess liquid to a minimum.

Ingredients

Roast The Zucchini

• 900 g zucchini, about 3 medium zucchini
• 1 tablespoon olive oil
• Salt, to taste
• Black pepper, to taste

For the Meat Sauce

• 1 tablespoon olive oil
• 450 g lean ground beef
• 1 small onion, finely diced
• 3 garlic cloves, minced
• 1½ cups passata
• 2 teaspoons Italian seasoning
• 1 teaspoon paprika
• ½ teaspoon salt
• ½ teaspoon black pepper
• ¼ teaspoon red pepper flakes, optional

For the Cheese and Toppings

• 2½ cups shredded low-moisture mozzarella
• ½ cup finely grated Parmesan
• 20–25 pepperoni slices
• ½ green bell pepper, finely diced
• ¼ cup sliced black olives, optional
• Fresh basil, optional

Equipment

Use a medium baking dish that is about 6 cm deep.

You’ll also need a large baking tray, parchment paper, a large skillet, and a sharp knife or mandoline.

How to Make Cheesy Pizza Zucchini Bake

1. Slice the zucchini

Preheat the oven to 425°F (220°C).

Trim the ends from the zucchini and cut each zucchini crosswise in half. Slice each half lengthwise into ¼-inch (6 mm) thick planks using a sharp knife or mandoline.

Cutting the zucchini in half first makes the planks easier to handle and gives you pieces that fit neatly into a square baking dish.

2. Roast the zucchini

Line a large baking tray with parchment paper.

Arrange the zucchini planks in a single layer. Lightly brush or spray both sides with olive oil and season with salt and black pepper.

Roast for 10–12 minutes, until the zucchini is just tender and has started to lose some moisture. It should not be browned or mushy.

Remove from the oven and set aside.

Tip: If your zucchini is especially large or watery, lightly salt the slices and let them stand for 20 minutes before roasting. Pat them dry with paper towels before placing them on the baking tray. This extra step helps remove excess moisture.

Air Fryer Option: Arrange the zucchini planks in a single layer in the air fryer basket. Air fry at 400°F (200°C) for 5–7 minutes, working in batches if necessary, until just tender and slightly dried.

3. Make the meat sauce

While the zucchini is roasting, heat 1 tablespoon olive oil in a large skillet over medium-high heat.

Add the diced onion and garlic and cook for 4–5 minutes, until softened.

Add the ground beef and cook until browned, breaking it up with a wooden spoon as it cooks.

Drain excess fat if necessary.

Add the passata, Italian seasoning, paprika, salt, black pepper, and red pepper flakes, if using.

Bring to a simmer, then cook uncovered for 15–20 minutes, stirring occasionally.

The finished sauce should be thick, not runny. You should be able to drag a spoon through it and briefly see the bottom of the pan.

Tip: If using thick store-bought pizza sauce instead of passata, stir it into the cooked beef and simmer for only 2–3 minutes.

4. Assemble the casserole

Lightly grease the 21 × 21 × 6 cm baking dish.

Start with a thin layer of meat sauce covering the bottom of the dish. This prevents the zucchini from sitting directly against the glass and gives the casserole a flavorful base.

Next, layer:

1. Half of the roasted zucchini
2. Half of the remaining meat sauce
3. 1 cup mozzarella
4. Remaining zucchini
5. Remaining meat sauce
6. Remaining mozzarella
7. Parmesan
8. Pepperoni
9. Diced bell pepper
10. Black olives, if using

Place the Parmesan directly beneath the pizza toppings so it can brown and create a flavorful golden top.

5. Bake

Reduce the oven temperature to 400°F (200°C).

Bake for 20–25 minutes, until the cheese is melted and bubbling.

For a golden pizza-style finish, switch the oven to broil for 2–3 minutes. Watch it closely because the cheese and pepperoni can brown quickly.

6. Rest before slicing

Remove the casserole from the oven and let it rest for 10–15 minutes before cutting.

This gives the cheese time to set and allows the layers to firm up, making the casserole much easier to serve neatly.

Recipe Tips for Zucchini Casserole

Roast the zucchini first

Zucchini contains a lot of water, and it releases moisture as it cooks. Roasting the slices before assembling the casserole helps evaporate some of that moisture before it reaches the baking dish.

Don’t skip the thick meat sauce

Reduce the passata before adding it to the casserole. A watery meat sauce combined with raw zucchini is one of the easiest ways to end up with liquid pooling at the bottom.

Use low-moisture mozzarella

Low-moisture mozzarella melts well without contributing as much liquid as fresh mozzarella.

Don’t cover the casserole

Bake it uncovered so steam can escape rather than becoming trapped inside the dish.

Let it rest

Don’t cut into the casserole immediately. Give it 10–15 minutes to settle so the layers have time to firm up.

Can I Use Pizza Sauce Instead of Passata?

Yes. If you already have pizza sauce, you can use it instead of passata. Since the pizza sauce is already thick, simply stir it into the browned beef and simmer for 2–3 minutes.

If you’re using passata, simmer the meat mixture uncovered for 15–20 minutes until thick.

Passata is the more economical option because you can use it directly in the meat sauce without buying a separate pizza sauce.

Can I Make This Zucchini Pizza Bake in an Air Fryer?

You can use an air fryer to prepare the zucchini.

Air fry the zucchini planks at 400°F (200°C) for 5–7 minutes, working in batches so the slices aren’t crowded.

For the casserole itself, use a conventional oven so the entire dish heats evenly and the cheese has enough time to melt and brown.

Can I Change the Pizza Toppings?

Absolutely.

Use any toppings you would normally put on pizza, as long as they aren’t excessively wet.

Good options include:

• Mushrooms
• Jalapeños
• Red onion
• Cooked Italian sausage
• Cooked chicken
• Ham
• Extra bell pepper
• Black olives
• Fresh basil

For watery vegetables such as mushrooms, cook them first so they don’t add excess moisture to the casserole.

Can I Make It Ahead?

Yes. Assemble the casserole, cover, and refrigerate for up to 24 hours before baking.

For the best texture, allow the chilled casserole to sit at room temperature for about 15–20 minutes while the oven preheats, then bake until heated through and bubbling.

How to Store Leftovers

Store leftovers in an airtight container in the refrigerator for up to 4 days.

Reheat individual portions in the microwave or reheat the casserole uncovered in a 350°F (175°C) oven until hot.

The casserole tends to become even firmer after refrigeration, making leftovers particularly easy to portion.

Is Zucchini Pizza Bake Low Carb?

Yes. This recipe is naturally low in carbohydrates because it replaces the traditional pizza crust with zucchini.

The exact carbohydrate content will depend on the passata, mozzarella, pepperoni, and toppings you use.

Nutrition

Approximate nutrition per serving, based on 6 servings:

• Calories: 400–420 kcal
• Protein: 34–35 g
• Carbohydrates: 10–11 g
• Fiber: 2–3 g
• Fat: 25–27 g

Nutrition will vary depending on the beef percentage, cheese, pepperoni, passata, and optional toppings used.

Frequently Asked Questions

How do you keep zucchini casserole from getting watery?

The best approach is to remove some of the zucchini’s moisture before assembling the casserole. For this recipe, roast the zucchini first, then simmer the passata-based meat sauce uncovered until thick.

If your zucchini is particularly large or watery, salt it for 20 minutes and pat it dry before roasting.

Do you have to salt zucchini before making zucchini casserole?

Not always. Medium zucchini can be roasted directly after seasoning. However, if your zucchini is unusually large or watery, salting it first helps draw out additional moisture.

Can you use sliced zucchini instead of shredded zucchini for pizza casserole?

Yes. Sliced zucchini works particularly well when cut into lengthwise planks. The planks create distinct layers and give the casserole a lasagna-like structure.

What size baking dish is best for zucchini pizza casserole?

For this recipe, a 21 × 21 cm square baking dish that is about 6 cm deep gives the casserole a good balance of height and surface area. It produces substantial layers without making the bake look too shallow.

Why is my zucchini casserole watery?

The most common causes are very watery zucchini, a thin tomato sauce, overcrowding the zucchini during roasting, or cutting into the casserole immediately after baking.

Roast the zucchini first, reduce the meat sauce until thick, bake uncovered, and allow the casserole to rest before serving.

Serving Suggestions

Serve this zucchini pizza bake with a simple green salad, roasted vegetables, or steamed broccoli for an easy weeknight dinner.

For a family pizza night, put extra toppings on the table and let everyone add their favorites to individual portions.

The Bottom Line

Cheesy Pizza Zucchini Bake gives you the flavors of pizza in a hearty, high-protein zucchini casserole—with no pizza dough and no complicated ingredients.

The secret to getting the texture right is simple: roast the zucchini first and reduce the passata-based meat sauce until thick.

Then layer, cover with plenty of cheese and pizza toppings, and bake until bubbling and golden.