Irresistible Pizza Casserole with Shredded Zucchini

If you ask me, pizza casserole is one of those meals that just makes sense.

This comforting dish takes everything you love about pizza and turns it into an easy weeknight dinner that sneaks in some extra vegetables. Shredded zucchini forms a surprisingly sturdy crust that holds up to all your favorite toppings.

It’s layered with seasoned ground beef, tangy tomato sauce, and plenty of melted cheese. Green peppers and onions add that classic pizza flavor everyone recognizes.

It’s a family-friendly meal that feels a little indulgent but won’t leave you feeling weighed down after dinner.

What Kind of Zucchini Should I Use?

For this pizza casserole, medium-sized zucchini work best since they’re easier to shred and have fewer seeds than the larger ones. You can use green zucchini, yellow summer squash, or a mix of both – they all taste pretty similar once cooked and will give you that same great texture. If your zucchini are on the larger side, you might want to scoop out some of the seeds before shredding since they can add extra moisture to your casserole. Make sure to salt and drain your shredded zucchini like the recipe calls for, as this step is key to preventing a watery dish.

Options for Substitutions

This recipe is pretty forgiving when it comes to swaps, so here are some options:

• Zucchini: This is the base of the casserole, so I wouldn’t recommend substituting it. The shredded zucchini creates the ‘crust’ that holds everything together. Make sure to squeeze out excess moisture after salting to prevent a soggy casserole.
• Ground beef: Feel free to use ground turkey, ground chicken, or Italian sausage instead. You could also try a mix of half beef and half sausage for extra flavor.
• Cheese blend: The mozzarella and cheddar combo is great, but you can mix things up with provolone, Monterey Jack, or Italian blend cheese. Just keep the total amount of cheese the same for best results.
• Italian tomato sauce: Regular tomato sauce or marinara sauce works just fine. You can even use pizza sauce if that’s what you have in the pantry.
• Bell pepper: Any color bell pepper works here, or you can leave it out if you’re not a fan. Mushrooms or olives would also be good additions if you want to switch things up.
• Onion: Yellow, white, or sweet onions all work equally well. In a pinch, you can use 1 teaspoon of onion powder mixed in with the beef.

Watch Out for These Mistakes While Baking

The biggest mistake you can make with this casserole is skipping the step where you salt and squeeze the zucchini – if you don’t remove that excess moisture, you’ll end up with a watery, soggy crust that won’t hold together. Make sure to really squeeze that zucchini hard in a clean kitchen towel or cheesecloth until barely any liquid comes out. Another common error is not pre-baking the zucchini crust long enough, so give it the full 20 minutes until it’s set and lightly golden before adding your toppings. Finally, don’t drain your ground beef halfway – let it brown completely and then drain off all the fat, otherwise the grease will pool on top of your casserole and make it greasy instead of cheesy and satisfying.

What to Serve With Pizza Casserole?

This pizza casserole is pretty hearty on its own, but I love serving it with a simple side salad tossed with Italian dressing to balance out all that cheesy goodness. Garlic bread or breadsticks are always a hit too, especially if you want something to scoop up any extra sauce on your plate. If you’re feeding a crowd, you could also put out some raw veggies like carrots, celery, and cherry tomatoes with ranch dip as a lighter side option. For a complete Italian-inspired meal, a Caesar salad with crunchy romaine and homemade croutons pairs really nicely with the casserole’s pizza flavors.

Storage Instructions

Store: This pizza casserole is great for leftovers throughout the week. Just cover it tightly with foil or transfer to an airtight container and keep it in the fridge for up to 4 days. It actually tastes even better the next day once all the flavors have had time to meld together!

Freeze: You can freeze this casserole either before or after baking. Wrap it well in plastic wrap and then foil, and it’ll keep for up to 3 months. I like to cut it into individual portions before freezing so I can grab just what I need for a quick dinner.

Reheat: Warm up leftovers in the oven at 350°F for about 15-20 minutes until heated through, or microwave individual portions for 2-3 minutes. If reheating from frozen, let it thaw in the fridge overnight first for best results.

Estimated Nutrition

Estimated nutrition for the whole recipe (without optional ingredients):

• Calories: 1800-2000
• Protein: 130-150 g
• Fat: 110-125 g
• Carbohydrates: 60-75 g

Ingredients

For the zucchini base:

• 4 cups zucchini (shredded and squeezed dry to prevent a soggy crust)
• 3/4 tsp salt
• 2 eggs
• 1/2 cup parmesan (I always use Kraft grated parmesan for this)
• 1 cup mozzarella
• 3/4 cup cheddar

For the topping:

• 1 lb beef (browned and drained)
• 1/2 cup onion
• 1 tsp Italian seasoning
• 1/2 tsp garlic powder
• 15 oz tomato sauce (I prefer Hunt’s for the best consistency)
• 1 cup mozzarella
• 3/4 cup cheddar
• 1 green pepper (diced into 1/2-inch pieces)

Step 1: Prepare the Zucchini Crust Base

• 4 cups zucchini
• 3/4 tsp salt
• 2 eggs
• 1/2 cup parmesan
• 1/2 cup mozzarella
• 3/8 cup cheddar

Shred the zucchini and place it in a colander, then sprinkle with salt and let it sit for 10 minutes—this draws out excess moisture that would make your crust soggy.

After 10 minutes, squeeze the zucchini firmly with your hands or wrap it in a clean kitchen towel and press out as much liquid as possible.

In a bowl, combine the squeezed zucchini with eggs, Parmesan cheese, and half of the mozzarella and cheddar.

Mix until everything is evenly incorporated, then press this mixture firmly into a 9×13 inch baking dish, creating an even layer that will serve as your crust.

Step 2: Pre-Bake the Zucchini Crust

• zucchini crust mixture from Step 1

Preheat your oven to 400°F if you haven’t already.

Bake the pressed zucchini mixture for 20 minutes until it’s set and beginning to firm up.

While the crust bakes, you’ll have time to prepare the meat sauce in the next step, keeping your workflow efficient.

Step 3: Brown the Beef and Build the Sauce

• 1 lb beef
• 1/2 cup onion
• 1 tsp Italian seasoning
• 1/2 tsp garlic powder
• 15 oz tomato sauce

While the crust bakes, heat a large skillet over medium-high heat and add the ground beef along with the diced onion.

Cook, stirring occasionally and breaking up the beef as it browns, until the meat is fully cooked and the onion is softened, about 8-10 minutes.

Drain off any excess fat by pouring the mixture through a colander or pushing it to the side of the pan and tilting to drain the grease.

Return the drained beef and onion to the skillet, then stir in the Italian seasoning and garlic powder to bloom the spices for about 30 seconds.

Pour in the tomato sauce and stir to combine, creating a rich, seasoned sauce.

Step 4: Layer and Top the Casserole

• beef and sauce mixture from Step 3
• 1 cup mozzarella
• 3/8 cup cheddar
• 1 green pepper

Once the zucchini crust has baked for 20 minutes and is set, remove it from the oven and pour the beef and tomato sauce mixture evenly over the top.

I like to use a spatula to spread it in an even layer so every bite gets some sauce.

Sprinkle the remaining mozzarella and cheddar cheese over the sauce, then scatter the diced green pepper pieces across the top for color and freshness.

Step 5: Final Bake and Rest

• assembled casserole from Step 4

Return the casserole to the 400°F oven and bake for 20 minutes until the cheese is melted and bubbly and the edges are lightly golden.

Let the casserole rest for 5 minutes out of the oven before serving—this helps the crust set slightly so it holds together when you cut into it.

Irresistible Pizza Casserole with Shredded Zucchini

Delicious Irresistible Pizza Casserole with Shredded Zucchini recipe with step-by-step instructions.

Print Recipe Pin Recipe

Prep Time 20 minutes mins

Cook Time 40 minutes mins

Total Time 1 hour hr 2 minutes mins

Servings: 8 servings

Calories: 1900

Ingredients Method

Ingredients

  

For the zucchini base

• 4 cups zucchini (shredded and squeezed dry to prevent a soggy crust)
• 3/4 tsp salt
• 2 eggs
• 1/2 cup parmesan (I always use Kraft grated parmesan for this)
• 1 cup mozzarella
• 3/4 cup cheddar

For the topping

• 1 lb beef (browned and drained)
• 1/2 cup onion
• 1 tsp Italian seasoning
• 1/2 tsp garlic powder
• 15 oz tomato sauce (I prefer Hunt's for the best consistency)
• 1 cup mozzarella
• 3/4 cup cheddar
• 1 green pepper (diced into 1/2-inch pieces)

Method

 

1. Shred the zucchini and place it in a colander, then sprinkle with salt and let it sit for 10 minutes—this draws out excess moisture that would make your crust soggy. After 10 minutes, squeeze the zucchini firmly with your hands or wrap it in a clean kitchen towel and press out as much liquid as possible. In a bowl, combine the squeezed zucchini with eggs, Parmesan cheese, and half of the mozzarella and cheddar. Mix until everything is evenly incorporated, then press this mixture firmly into a 9x13 inch baking dish, creating an even layer that will serve as your crust.
2. Preheat your oven to 400°F if you haven't already. Bake the pressed zucchini mixture for 20 minutes until it's set and beginning to firm up. While the crust bakes, you'll have time to prepare the meat sauce in the next step, keeping your workflow efficient.
3. While the crust bakes, heat a large skillet over medium-high heat and add the ground beef along with the diced onion. Cook, stirring occasionally and breaking up the beef as it browns, until the meat is fully cooked and the onion is softened, about 8-10 minutes. Drain off any excess fat by pouring the mixture through a colander or pushing it to the side of the pan and tilting to drain the grease. Return the drained beef and onion to the skillet, then stir in the Italian seasoning and garlic powder to bloom the spices for about 30 seconds. Pour in the tomato sauce and stir to combine, creating a rich, seasoned sauce.
4. Once the zucchini crust has baked for 20 minutes and is set, remove it from the oven and pour the beef and tomato sauce mixture evenly over the top. I like to use a spatula to spread it in an even layer so every bite gets some sauce. Sprinkle the remaining mozzarella and cheddar cheese over the sauce, then scatter the diced green pepper pieces across the top for color and freshness.
5. Return the casserole to the 400°F oven and bake for 20 minutes until the cheese is melted and bubbly and the edges are lightly golden. Let the casserole rest for 5 minutes out of the oven before serving—this helps the crust set slightly so it holds together when you cut into it.