Ultimate Baked Pizza Casserole

A cheesy, saucy, hearty baked casserole loaded with seasoned ground beef, pepperoni, vegetables, and plenty of melted mozzarella. It has all the comforting flavors of pizza in an easy one-dish meal.

 Ingredients

Casserole

• 1 lb (450 g) ground beef
• 1 small onion, diced
• 3 cloves garlic, minced
• 1 medium zucchini, diced
• 1 small bell pepper, diced
• 1 cup sliced mushrooms
• 1½ cups marinara or pizza sauce
• 1 tsp Italian seasoning
• ½ tsp dried oregano
• ½ tsp garlic powder
• ½ tsp paprika
• Salt and black pepper, to taste
• 1 cup sliced pepperoni, halved
• 1½ cups shredded mozzarella cheese
• ½ cup shredded cheddar cheese
• ¼ cup grated Parmesan
• 1 tbsp olive oil

Optional toppings

• Sliced black olives
• Banana peppers
• Jalapeños
• Cherry tomatoes
• Fresh basil
• Red pepper flakes

 Instructions

1. Prepare the oven

Preheat oven to 375°F (190°C).

Lightly grease a 9 × 13-inch baking dish with olive oil.

2. Brown the beef

Heat a large skillet over medium-high heat.

Add the ground beef and onion. Cook for 6–8 minutes, breaking the beef apart as it cooks.

Drain excess grease if necessary.

Add garlic and cook for another 30–60 seconds.

3. Add the vegetables

Add zucchini, bell pepper, and mushrooms.

Cook for 4–5 minutes, just until the vegetables begin to soften.

Season with Italian seasoning, oregano, garlic powder, paprika, salt, and pepper.

4. Add the sauce

Pour in the marinara or pizza sauce.

Stir everything together and simmer for 2–3 minutes.

Remove from the heat.

5. Assemble the casserole

Spread half of the meat mixture into the prepared baking dish.

Add half of the pepperoni and half of the mozzarella.

Spread the remaining meat mixture over the top.

Finish with the remaining pepperoni, mozzarella, cheddar, and Parmesan.

6. Bake

Cover loosely with foil and bake for 20 minutes.

Remove the foil and bake another 10–15 minutes, until the cheese is bubbling and golden.

For an extra-browned top, broil for 1–2 minutes, watching carefully.

7. Rest and serve

Let the casserole rest for 5–10 minutes before serving.

Top with fresh basil or red pepper flakes if desired.

 Quick Recipe Information

• Prep time: 15 minutes
• Cook time: 35–40 minutes
• Total time: About 55 minutes
• Servings: 6–8
• Difficulty: Easy

 Tips for the Best Pizza Casserole

• Drain excess grease from the beef so the casserole isn’t oily.
• Don’t overcook the zucchini before baking—it will continue cooking in the oven.
• Use low-moisture mozzarella for the best cheesy topping.
• Let it rest before slicing so the layers set.
• For a crispier cheese topping, broil briefly at the end.

 Easy Variations

Low-Carb/Keto:
Use a no-sugar-added pizza sauce and add extra zucchini, mushrooms, or cauliflower instead of pasta.

Chicken Pizza Casserole:
Replace ground beef with 3 cups shredded cooked chicken.

Supreme Pizza:
Add mushrooms, bell peppers, olives, onions, and Italian sausage.

Spicy:
Add jalapeños, crushed red pepper, and spicy Italian sausage.

Vegetarian:
Skip the meat and increase the mushrooms, zucchini, peppers, and spinach.

 Nut & Allergen Information

• Contains: Milk/dairy.
• Potential allergens: Check the labels on pepperoni, marinara sauce, and seasonings for wheat or other additives.
• Nut-free: The recipe is naturally nut-free when all packaged ingredients are produced without nut-containing ingredients.
• Gluten-free: It can be gluten-free, but choose certified gluten-free sauce, pepperoni, and seasonings and check labels for cross-contact.

Approximate Nutrition

Per serving, assuming 8 servings:

• Calories: ~390
• Protein: ~27 g
• Carbohydrates: ~10 g
• Fat: ~27 g
• Fiber: ~2–3 g

Nutrition varies depending on the brands and exact ingredients used.

 Q&A

Can I make this ahead of time?
Yes. Assemble the casserole, cover, and refrigerate for up to 24 hours. Add about 5–10 minutes to the baking time if baking directly from the refrigerator.

Can I freeze it?
Yes. Cool completely, portion into airtight containers, and freeze for up to 2–3 months.

Can I use ground turkey?
Absolutely. Ground turkey makes a lighter version while still providing plenty of protein.

Can I make it without pepperoni?
Yes. Replace it with cooked sausage, chicken, turkey pepperoni, or additional vegetables.

How do I reheat leftovers?
Microwave individual portions until hot, or reheat in a 350°F (175°C) oven for about 15 minutes.

What should I serve with it?
A green salad, roasted vegetables, steamed broccoli, or garlic-roasted zucchini makes a great side.

 Serving Idea

Serve a hot square of pizza casserole with a crisp green salad and a little extra Parmesan. It’s especially good for family dinners, meal prep, potlucks, and busy weeknights.