To make a pizza, heat the oven to 425°. Sprinkle a large baking sheet with cornmeal. Punch down the dough, halve it, and roll each portion into a ball. Let them rest 10 minutes, then flatten and roll one ball into a 12-by 16-inch rectangle. (The other portion can be frozen for up to one month.) Transfer the dough to the prepared sheet, add toppings, and bake until the dough is lightly browned and crisp, about 15 minutes.