First: Add a little salt and oil. When cooking the freshly wrapped jiaozi, some salt and oil will be added to prevent it from rotting. Similarly, when cooking and freezing jiaozi, it is necessary to put a small amount of salt and oil, which can have different effects on jiaozi.
Second: soak in cold water for one minute and then cook. The surface of frozen dumplings is very hard and may even contain ice. Soak the dumplings in cold water for one minute, and the skin of the frozen dumplings will quickly soften and absorb some water, which will increase the ductility of jiaozi. So before cooking, soak the frozen dumplings in cold water for one minute. But one thing, if jiaozi is soaked for too long, jiaozi may stick together, and it is very easy to rot when cooked.
Third: Cook in a pot with warm water. This is the biggest difference between boiling frozen jiaozi and boiling fresh jiaozi. Fresh dumplings that have just been wrapped can be boiled. For frozen jiaozi, you can't boil the pot with water. In addition, jiaozi can't be directly cooked with cold water. The low water temperature leads to the gelatinization of the starch on the dumpling skin, just like dry flour will naturally stick to the pot or stick to each other when it meets water.