Use a big fire first, then a small fire. When cooking jiaozi, the fire quickly boiled the water. When water boils, it becomes a small fire. The water temperature can be controlled at about 100 degrees, and the cooking time should be enough. After jiaozi floats completely, wait for a few minutes to keep jiaozi ripe. It is necessary to add cold water. Boiling the skin with big fire and filling it with small fire can make jiaozi heated evenly, and it is not easy to break the skin.