
When you are craving hot cheesy pizza flavors but want something comforting and lower in carbs this low carb pizza casserole hits the spot. Packed with Italian sausage, mushrooms, green pepper and pepperoni nestled among tender cauliflower and gooey mozzarella, it feels totally indulgent while still fitting a lighter lifestyle.
My crew always lights up for pizza night and this hearty casserole quickly took center stage. I first made it as a clean-out-the-fridge meal and now it is a monthly favorite for busy weeknights.
Ingredients
- Cauliflower florets: Cut into bite-size pieces Brings bulk and nutrition while soaking up all the pizza flavors Choose firm tight florets with no dark spots
- Pepperoni: Adds meaty spicy bites Go for natural brands with minimal additives
- Italian Sausage: Choose a spicy or mild version in bulk or in casings Remove from casing for quicker cooking Seek out sausage with good marbling for flavor
- Olive Oil: Helps sauté the mushrooms and brings extra richness Go for extra virgin if possible
- Mushrooms: Sliced for earthy depth of flavor Cremini or white button mushrooms work well Look for smooth firm caps
- Green Pepper: Adds freshness and crunch Choose one that feels heavy with vibrant skin
- Mozzarella cheese: Shredded creates the gooey pizza stretch Opt for whole milk mozzarella for melt and flavor
- Low Carb Pasta Sauce: I like Rao’s for its balanced taste and low sugar but any lower carb marinara works Check the label for no added sugars
- Parmesan cheese: Powdered adds savory sharpness Freshly grated for best impact
- Italian Seasoning: Brings classic pizza herb flavors Use a good dried blend or homemade if you like
Step-by-Step Instructions
- Steam the Cauliflower:
- Place the bite-size cauliflower florets in a microwave safe bowl with a cup of water Cover with a damp paper towel and microwave on high for about three minutes or until the cauliflower is just tender Test with a fork so that it is firm but cooked through Drain well then pat the florets fully dry with a paper towel to avoid watery casserole Set aside
- Brown the Sausage:
- Preheat your oven to four hundred degrees Fahrenheit In a large skillet over medium high heat add the Italian sausage Cook it for about fifteen minutes stirring to break up large pieces Once beautifully browned and cooked through drain off excess fat so your casserole stays rich without being greasy Set aside
- Sauté the Mushrooms:
- In the same skillet pour in the olive oil over medium high heat Add the sliced mushrooms and let them sauté for ten minutes until they have released their water and are turning golden Stir occasionally and do not overcrowd so they caramelize properly Remove and set aside
- Prep the Casserole Dish:
- Spray a thirteen by nine inch casserole dish with non-stick spray Spread half a cup of pasta sauce evenly across the bottom so your flavors start with every bite
- Mix and Layer Ingredients:
- In a large mixing bowl toss together the steamed cauliflower cooked sausage sautéed mushrooms and chopped green pepper Mix so everything is well distributed throughout the casserole For the first layer spread half this mixture in your dish Top with half a cup of pasta sauce layer on half the pepperoni slices pressing them gently between the toppings and sprinkle with half the mozzarella cheese
- Repeat the Layering:
- Place the remaining veggie and meat mixture on top followed by the last of the pepperoni keeping ten slices aside for the top Drizzle with remaining pasta sauce and finish off with the rest of the mozzarella
- Add Cheesy Topping:
- In a small bowl stir together the powdered Parmesan and Italian seasoning Sprinkle this cheesy mix evenly over your casserole artfully arrange those ten pepperoni slices on top to finish
- Bake Until Bubbling:
- Place your casserole uncoverered in the oven on a center rack Bake for thirty minutes or until hot throughout and the cheese is bubbling and melted Let rest for a few minutes before serving for easiest slicing

One thing I look forward to is the delicious browned cheesy edge you get from the mozzarella on top That golden crust always draws family to sneak bites while this rests out of the oven It is a small battle of forks every time
Storage Tips
Leftovers keep well in the fridge for up to four days Cool completely before storing then cover tightly or spoon into airtight containers For longer storage this casserole freezes well for up to two months Wrap portions tightly in plastic wrap then bag for easiest reheating Thaw overnight before microwaving or warming gently in the oven
Ingredient Substitutions
You can switch up the meat easily If you do not have Italian sausage try ground beef turkey or even a plant-based sausage Skip the pepperoni for a lighter casserole or use turkey pepperoni for less fat No green pepper available Try red or yellow peppers or add some sliced black olives for a different flavor
Serving Suggestions
This pizza casserole is a full meal on its own but it shines with a simple side salad finished with olives or a tangy vinaigrette Add roasted broccoli or sautéed spinach for a big plate of color If you want more texture toss in a handful of chopped artichoke hearts or sun-dried tomatoes before baking

Once you try this casserole you will find it is a reliable go to for both family gatherings and solo meal prep nights The edge pieces disappear fastest in our house and nobody ever misses the crust
Frequently Asked Questions
- → How do I prevent the casserole from becoming watery?
Make sure to steam the cauliflower only until tender and pat dry thoroughly before assembling. Also, sauté mushrooms well to release excess moisture.
- → Can I substitute the Italian sausage?
Yes, use ground turkey, beef, or a vegetarian sausage alternative to suit your preference while maintaining the dish’s flavor profile.
- → What type of pasta sauce works best?
Choose a low carb, sugar-free marinara for the richest flavor, such as Rao’s Homemade Marinara, or use any favorite marinara with minimal added sugars.
- → How can I make this dish spicier?
Spice things up by using hot Italian sausage or adding a pinch of crushed red pepper flakes to your meat mixture before baking.
- → Is this casserole freezer friendly?
Yes. Cool completely, wrap tightly, and freeze. Reheat in the oven until warmed through for best texture and flavor.
- → Can I add more vegetables?
Absolutely. Try adding spinach, black olives, or onions for extra taste and nutrition without affecting the low carb content significantly.