Dessert pizza is the ultimate in anything-goes sweet treats for the grill. Start with a premade pizza crust or flatbread, then brush it with melted butter or oil before piling on the toppings. Go gourmet with a fruit and cheese combination, or if you prefer more traditional desserts, keep things simple with cinnamon, sugar and melted butter for a sweet, French toast-style dish. You can also add chocolate or caramel sauce, chopped fruit, chocolate chips or your favorite bite-sized candies. Line the top of the grill with foil before cooking, or place your pizza on a cookie sheet for even, consistent grilling.