Wash the pigskin with cold water and put it into the pot. After boiling, continue to cook for five minutes, skimming off oil and impurities. Take out the pigskin and scrape the lard off the inside of the pigskin while it is hot. Lard will be more solidified and slippery when it is cold. Cut into small strips, then put hot water in the pot, put the skin in, cook for two or three minutes, and skim off the oil slick. The purpose of degreasing is to make the frozen skin clean and bright, otherwise it will make the soup turbid and feel greasy.
Pour warm water into the pot, the amount of which is about 2.5 times that of pigskin, turn on low heat, cover the pot and cook until the ratio of water to pigskin is about 1: 1.5. Pour into a container, cool, and refrigerate 12 hours.
Tip: There are two ways to season. One is to add seasoning directly when cooking pigskin, put pepper, star anise and onion into seasoning bag, add soy sauce and cook with pigskin. I prefer this method, because it tastes stronger at home, and it is very convenient to simply season it with vinegar and minced garlic before eating.
If you want to be clean, you can soak the sliced skin in baking soda for two hours, and the jelly is very smooth and appetizing.