Some "fake fish maws" are made from air-dried pig skin that has been expanded. The main preparation method is: first wash the air-dried pig skin with warm alkaline water, cut it into small strips, and add In a warm oil pan, do not let the oil boil or smoke. Continue for 2-3 hours. When the meat skin changes from hard to soft, take it out. At this time, boil the oil, then put in the soft pig skin that has been braised in the oil. Pick it up after it foams and expands.