Preheat the oven to 400ºF. Spray a 9x9 casserole pan with cooking spray.
Place the cauliflower onto a sheet pan and drizzle with oil, salt, and pepper. Bake for 15-20 minutes or until the cauliflower has softened.
In a small pot, combine the heavy cream, cheddar, cream cheese, dijon, garlic, and paprika. Heat the mixture over medium heat until it is smooth about 5 minutes, making sure you stir often. Season the sauce with salt and pepper to taste.
Stir the roasted cauliflower and mozzarella cheese into the sauce, transfer the mixture to the casserole pan. Top the dough with parmesan cheese and place it back into the oven for 5 to 10 minutes until the cheese has melted.