I make this pizza casserole when I want all the flavors of pizza night without the crust or the carbs. It's hearty, cheesy, and packed with flavor from Italian sausage, peppers, mushrooms, and plenty of gooey melted cheese.
You'll love this casserole because it's simple, customizable, and family-approved. It's perfect for busy weeknights, easy to meal prep, and can be made with whatever pizza toppings you love most all in one baking dish.
Bonus! Our version gets layered twice so every bite is loaded with toppings and melted cheese. It's the perfect family dinner when you're craving comfort food but keeping it low carb.
Things to Know Before Making Pizza Casserole
- Use quality marinara sauce: Rao's has no added sugar and gives the best flavor for low-carb recipes.
- Brown the sausage well: It adds depth and helps prevent extra grease in the casserole.
- Shred your own cheese: Freshly shredded cheese melts better and reduces carbs.
- Customize the toppings: Add or skip veggies to make it your own version of pizza night.
Since 2018 I've been creating easy, high-protein, family-friendly casseroles and we've tested this low carb pizza casserole many times. It always turns out cheesy, hearty, and satisfying.
My other favorite easy low carb casseroles includes High Protein Taco Casserole, Keto Cheeseburger Casserole, and this Hamburger Green Bean Casserole.
Ingredients Overview
- Italian sausage: Adds bold flavor; you can swap half for ground beef or chicken sausage if preferred.
- Garlic: Builds a rich, savory base.
- Red onion: Adds sweetness and flavor balance.
- Green and red bell peppers: Bring color and crunch to the casserole.
- Button mushrooms: Add a hearty, meaty texture.
- Italian seasoning: Classic herbs that tie everything together.
- Pepperoni: Gives it that true pizza flavor.
- Marinara sauce: Rao's is a great low-carb option that tastes homemade.
- Black olives: A classic pizza topping for salt and texture.
- Mozzarella cheese: Melts perfectly for a gooey topping.
- Cheddar cheese: Adds a mild sharpness that balances the mozzarella.
- Parmesan cheese: Finishes the casserole with a rich, salty flavor.
Full list with measurements is in the recipe card below.
How to Make Easy Pizza Casserole
Step 1: Preheat your oven to 425°F and lightly grease a 9x13-inch baking pan. Set aside.
Step 2: In a large skillet over medium-high heat, cook the Italian sausage until browned and cooked through. Remove from the skillet, keeping some grease in the pan. Add a little olive oil if needed before cooking the veggies.
Step 3: In the same skillet, sauté the garlic, chopped onions, bell peppers, mushrooms, and Italian seasoning until the vegetables are tender and fragrant.
Step 4: Layer half of each ingredient in the baking dish: sausage, sautéed veggies, marinara sauce, cheese, pepperoni, and black olives. Repeat the layers with the remaining ingredients.
Step 5: Bake for 15-20 minutes, until the cheese is melted and bubbly. For a golden top, broil for 1-2 minutes. Let rest for 5-10 minutes before serving.
Step 6: Top with red pepper flakes, chopped parsley, and extra parmesan if desired. Slice and serve warm.
Substitutions and Variations
- Swap half the sausage for ground beef, chicken sausage, or additional veggies for a lighter version.
- Use pizza sauce instead of marinara for a tangier flavor.
- Add extra cheese on top for a thicker, gooey layey or experiment with other cheeses like provolone, feta, or even some ricotta for a creamy touch..
- Stir in cooked cauliflower rice for more veggies and volume.
- Add in other pizza favorites like tomatoes, spinach, or artichokes.
- Make it spicy with some crushed red pepper flakes or diced jalapenos.
What to Serve with Pizza Casserole
This casserole is hearty enough on its own but pairs perfectly with Caesar Salad, Air Fryer Zucchini Fries, or Roasted Broccoli for a complete meal.
Storage and Reheating
Store leftovers in an airtight container for up to 4 days in the refrigerator. Reheat in the oven at 350°F until warm, or microwave individual portions. You can also freeze for up to 3 months and thaw in the fridge overnight before reheating.
FAQ's
Can I make this ahead of time?
Yes, you can assemble the casserole and refrigerate it up to a day in advance. Just pop it in the oven when you're ready to cook. If you're cooking it after making it in advance, it'll take longer to cook.
Is this keto-friendly?
Absolutely! Our pizza casserole recipe is low in carbs and high in protein, making it a great option for a keto diet. Feel free to cut out any ingredient such as onion or bell peppers to reduce the carbs even more.
What kind of cheese works best?
A mix of mozzarella, cheddar, and parmesan gives the best balance of melt and flavor.
More Low Carb Casseroles
- Low Carb Philly Cheese Steak Casserole
- Green Chicken Chili Casserole
- Keto Chicken Broccoli Casserole
- Ground Beef Zucchini Casserole
- Low Carb Chicken Enchilada Casserole
- Chicken Bacon Ranch Casserole
- Baked Chicken Parmesan Casserole
- 30 Easy Low Carb Casseroles
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Recipe
Keto Pizza Casserole Recipe
Ingredients
- 2 lb Italian sausage swap 1 lb for ground beef or chicken Italian sausage if preferred
- 3 garlic cloves minced
- ½ large red onion chopped
- 1 cup green pepper chopped
- 1 cup red bell pepper chopped
- 8 ounces button mushrooms sliced
- 1 tablespoon Italian seasoning
- 5 oz pepperoni
- 2 cups marinara sauce Rao's recommended
- 4 ounces black olives sliced
- 2 cups mozzarella cheese shredded
- 1 cup cheddar cheese shredded
- ½ cup parmesan cheese shredded
Instructions
- Preheat your oven to 425 F. Grease a 9x13 pan and set it aside.
- In a large skillet over medium-high heat, brown the Italian sausage until cooked through. Set it aside, leaving the grease in the pan (add olive oil if more grease is needed) to cook the veggies.
- In the same skillet, saute the garlic, sliced onions, bell peppers, mushrooms, and Italian seasoning until the veggies are tender.
- You're going to take half of the ingredients and layer them into the 9x13 pan and then repeat the layers with the other half of the ingredients. We made two layers in this order: ½ the ground sausage, ½ of the cooked veggies, 1 cup of marinara sauce, ½ the cheese, ½ the pepperoni, and 1 /2 of the black olives. Repeat these steps.
- Bake the pizza casserole for 15-20 minutes. Broil for 1-2 minutes if you want the cheese to be more golden in color. Let it rest for 5-10 minutes before serving.
- Garnish with red pepper flakes, chopped parsley, and more parmesan cheese, if desired. Enjoy!
Notes
- Shredding your own cheese is recommended, it melts better and is lower in carbs.
- This is an easy recipe to customize and make like your favorite pizza! Feel free to skip any of the vegetables or cut back on certain ones to reduce the carbs.
- To sneak in even more vegetables, mix in 1 lb sauteed or microwaved cauliflower rice.
- We recommend Rao's brand marinara sauce since it tastes homemade and it doesn't add sugar. For the lowest price, stock up at Costco or get it from Walmart, it's often 30% cheaper than a traditional grocery store. Feel free to substitute whatever your favorite brand of sauce is or use pizza sauce instead.
Jamie Mattern says
This is delicious! Can you tell me the nutritional value for this?
W says
Eating this now. YUM. Thank You