Prepare the Cauliflower: Steam the cauliflower florets until tender, about 3 minutes in the microwave. Drain excess water and pat dry.

Preheat the Oven: Preheat your oven to 400°F (200°C) to ensure even baking.

Cook the Sausage: In a skillet over medium heat, cook the Italian sausage for about 15 minutes until browned. Drain excess fat.

Sauté the Vegetables: Sauté mushrooms with olive oil for about 10 minutes until golden and tender.

Build the Base: Grease a 9x13-inch casserole dish and spread ½ cup of low carb pasta sauce across the bottom.

Mix the Fillings: In a large bowl, combine the steamed cauliflower, cooked sausage, sautéed mushrooms, and chopped green peppers.

First Layer of Ingredients: Spoon half of the mixture into the casserole dish, top with another ½ cup of low carb pasta sauce, half of the pepperoni, and 6 oz of mozzarella cheese.

Finish Layering: Add the remaining filling mixture, top with last pasta sauce, pepperoni, and the rest of the mozzarella cheese.

Season the Top: Mix Parmesan cheese with Italian seasoning and sprinkle over the top layer.

Bake: Bake in the preheated oven for 30 minutes until the cheese is bubbling and golden brown.