A pizza stone is a piece of unglazed ceramic or earthenware specifically used to cook pizzas on. The nature of the pizza stone and preheating it from a cold oven helps to distribute the heat evenly across the pizza base to create a crisp crust. Always put a pizza stone in a cold oven and then turn the oven on, letting it heat up along with the oven; adding a cold pizza stone to a hot oven can cause it to crack. Remember that once a pizza stone has been heated, the stone is too hot to handle, even with an oven glove. If you donβt have a pizza stone, it is possible to preheat a large oven tray for 30 minutes and use it in the same way.