Cast irons are known for things sticking if the skillet isn't seasoned well before using or it isn't maintained properly. But actually when they are taken care of, most things will not stick to the cast iron skillet. If you're worried about the pizza dough sticking to the skillet, don't be! I recommend coating the skillet with olive oil or vegetable oil before placing the dough into it as the recipe shows. It should easily loosen with a spatula once it comes out of the oven.