Do not use casseroles to cook vegetables. Generally, casseroles are used to cook soup and vegetables. Because the oil temperature in the casseroles is very high, when the oil in the casseroles is heated, it is suddenly put into cold dishes, and the pans are easy to crack. Therefore, when cooking, you should add water first, and then move it to the fire. If you burn the pot first and then put water, it will easily crack the pot. When using casserole to cook soup and stew meat, first put water into the casserole, then put the casserole on the fire, first use slow fire, and then use strong fire.