Easy Low Carb Keto Crustless Pizza Casserole

The first time I made this crustless pizza casserole, my husband actually asked where the pizza was hiding. When I told him the bubbling cheese and spicy sausage skillet was dinner, he looked skeptical, but one bite converted him completely. Now it is our Friday night staple that delivers everything we love about pizza without the carb crash that follows.

Last winter when we were doing a whole30 reset, I was desperate for something that felt indulgent but still fit our eating plan. This casserole saved us from giving up, and honestly, now I prefer it to actual pizza. The flavors concentrate beautifully without a crust getting in the way.

Ingredients

• Ground Italian sausage: The fennel and spices in the sausage give you that authentic pizza flavor base without any extra work
• Mushrooms: They release moisture as they cook and become little umami bombs that taste like they have been simmering in sauce for hours
• Sugar-free pizza sauce: Read those labels carefully because hidden sugars can add up fast on keto
• Mozzarella cheese: Shred it yourself if you can because pre-shredded has anti-caking agents that prevent that gorgeous melty stretch
• Cheddar cheese: Adds a sharpness that cuts through the richness of the sausage
• Parmesan cheese: The salty finish that makes every bite taste like a pizzeria visit
• Italian herbs: Dried herbs work better here than fresh because they stand up to the long bake time
• Red pepper flakes: Add these if you miss the little kick that pepperoni usually provides

Instructions

Preheat your oven to 400°F (200°C).

Give yourself time to let the oven fully heat because a hot start is what creates those gorgeous bubbly cheese patches.

Brown the sausage in a large skillet.

Cook it until really browned with some crispy bits, then drain most of the fat but leave about a tablespoon for flavor.

Add the vegetables.

Toss in mushrooms, peppers, onions, and garlic, then cook until everything softens and smells amazing.

Stir in sauce and seasonings.

Let everything simmer together for a few minutes so the flavors can start becoming friends.

Transfer to a baking dish.

Use a 9x9 inch dish and give it a quick spray with oil so nothing sticks.

Layer on the cheeses.

Sprinkle mozzarella and cheddar evenly, then finish with Parmesan and those pepperoni slices if you are using them.

Bake until bubbly.

About 20-25 minutes should do it, but keep an eye on it because all ovens behave differently.

Let it rest briefly.

Five minutes seems like forever when cheese is involved, but this helps portions hold together better.

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My daughter now requests this for her birthday dinner instead of going out for actual pizza. The fact that she can eat three servings without feeling stuffed makes both of us happy, and watching her friends try it for the first time never gets old.

Making It Your Own

Think of this as your pizza canvas. Sometimes I add black olives or roasted red peppers from a jar, and fresh spinach works beautifully if you want to sneak in some greens. The best version is whatever your family fights over the next day for leftovers.

Meal Prep Magic

This recipe actually tastes better on day two when all the flavors have had time to hang out together. I make a double batch on Sunday and portion it into containers for the easiest lunch week of my life. The cheese reheats perfectly and nothing gets soggy.

Serving Suggestions

A crisp green salad with a vinaigrette cuts through all that richness perfectly. Sometimes I serve it with roasted broccoli or zucchini noodles if I want something warm on the side. The key is keeping sides light so the casserole stays the star.

• Crushed red pepper on the table for heat lovers
• Fresh basil leaves added after baking for a pop of color
• Garlic powder dusted over the top during the last five minutes

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This recipe proves you do not have to sacrifice comfort food when you are eating low carb. Enjoy every cheesy, satisfying bite.

Recipe FAQ

→ Can I make this casserole dairy-free?

Yes, substitute dairy-free cheese alternatives for the mozzarella, cheddar, and Parmesan. Many brands melt well and provide similar texture. Ensure your pizza sauce is also dairy-free.

→ How long does this keep in the refrigerator?

Store leftovers in an airtight container for up to 4 days. Reheat in the microwave or oven at 350°F until heated through. The flavors often improve after a day or two.

→ Can I freeze this crustless pizza casserole?

Absolutely! Assemble the entire dish, wrap tightly with foil and plastic, then freeze for up to 3 months. Thaw overnight in the refrigerator before baking, or bake from frozen adding 15-20 minutes to the cooking time.

→ What vegetables work best in this casserole?

Mushrooms, bell peppers, and onions are classic choices. You can also add black olives, spinach, roasted red peppers, zucchini, or even broccoli. Avoid watery vegetables like fresh tomatoes unless you cook them down first.

→ Is this suitable for meal prep?

Perfect for meal prep! Portion into individual containers after cooling. The casserole reheats beautifully and maintains its texture. Consider making a double batch - it freezes exceptionally well for future quick meals.

→ Can I use fresh pizza sauce instead of sugar-free?

You can use regular pizza sauce, but it will increase the carbohydrate count significantly. For strict keto adherence, sugar-free marinara or make your own sauce with crushed tomatoes, garlic, and Italian herbs.