Frozen pizza is pizza that has been prepared beforehand, and is then deep-frozen, to be distributed in supermarkets. It is among the most successful and popular types of convenience food. It is prepared slightly differently: First the dough with the tomato sauce is pre-cooked, then the toppings are added. The dough of frozen pizza is different. Its dough also contains modified starch and leavening agents. This makes it possible to cook the pizza directly, without first defrosting it. One main frozen pizza brand is Digiorno. 