How to Make It
Preheat oven to 475°F. Cut 4 (1-inch) “steaks” from head of cauliflower, reserving florets from outer edges for another use. Trim most of the tough core from bottom.
Place cauliflower steaks on a rimmed baking sheet; brush both sides with oil, and sprinkle with salt and pepper. Bake in preheated oven until bottom is browned and slightly crisp around the edges, about 7 minutes. Flip cauliflower, and sprinkle each steak with 1 tablespoon of the Parmesan cheese, allowing excess to fall between the crevices onto baking sheet. Any cheese that falls to the bottom will help form a crust on the bottom...yum! Return to oven, and cook an additional 5 to 7 minutes or until golden.
Spread each steak with 1 tablespoon sauce, 2 tablespoons mozzarella, and 8 pepperoni pieces. Bake until cheese is melted and beginning to brown, about 5 minutes. Garnish with basil, if desired.