Preheat the oven to 450°F .
Bring a large pot of water to a boil. Season with 1⁄2 teaspoon of salt. Carefully drop the cauliflower into the boiling water. Cook for 8 minutes. Drain thoroughly, using paper towels to soak up any excess moisture.
Place the drained cauliflower into a food processor. Pulse for 1 minute until the cauliflower is “riced.”
Transfer the cauliflower to a large bowl. Add the egg, 1 cup of mozzarella cheese, the garlic powder, the remaining 1⁄4 teaspoon of salt, and pepper. Stir until the cheese fully melts.
Separate the cauliflower dough into two equal balls.
On a parchment-lined baking sheet, spread each ball into an 8-inch crust. The crust should be very thin.
Place the crusts in the preheated oven. Bake for 15 to 20 minutes, or until browned. The edges of the crust should almost be burned.
Remove the crusts from the oven. Turn the oven to broil.