Preheat your oven to 400°F (200°C). Line a baking sheet with parchment paper.

Cut the cauliflower into florets and pulse in a food processor until it resembles rice.

Steam the cauliflower rice for about 5 minutes until soft. Let it cool, then use a cheesecloth or kitchen towel to squeeze out as much moisture as possible.

In a bowl, combine the cauliflower, Parmesan cheese, mozzarella cheese, egg, salt, garlic powder, basil, and oregano. Mix well.

Press the mixture onto the prepared baking sheet to form a pizza crust. Bake for 10-12 minutes until golden brown.

Spread the marinara sauce over the baked cauliflower crust.

Sprinkle 1 cup of mozzarella cheese evenly over the sauce.

Arrange the diced bell peppers, broccoli florets, red onion, corn (if using), and diced tomatoes over the cheese.

Return the pizza to the oven and bake for an additional 8-10 minutes, or until the cheese is melted and bubbly.

Allow the pizza to cool slightly before slicing. Serve and enjoy the vibrant, nutrient-packed flavors of your Rainbow Pizza!