Preheat oven to 400 degrees. Spray a standard sized muffin pans with cooking spray.
Mix all of the crust ingredients together in a bowl until well combined.
Evenly distribute the cauliflower mixture into each well of the muffin tin, using about 2 heaping tablespoons in each one. Using your fingers, press the cauliflower into the bottom of the muffin pan to make an even layer.
Bake for 12 minutes until crust is slightly golden. Take the muffin pan out of the oven and top each crust with 1 teaspoon of marinara sauce, 1 tablespoon of mozzarella cheese and 1-2 tsp of pepperoni. Bake for an additional 8 minutes until the cheese is melted.