The oil should be preheated to 350°F/176°C for the best evenly cooked fried pizzas. If you don't have a thermometer, you can test the temperature by dropping a small piece of dough into the oil. If it sizzles and rises to the surface, the oil is ready. Alternatively, place a wooden chopstick into the middle of the oil and if bubbles rise up around it, the oil is ready.