1. You can fry the pig's trotters in oil (it's better if you use a little lard), so that the protein can melt into the soup later; 2. Boil the pig's trotters in cold water; 3. Water Put enough at one time and do not add water in the middle of cooking the soup; 4. Cover the pot and bring to a boil over high heat, then simmer over low heat; 5. Do not use a stainless steel pot when using a casserole; 6. Use an open flame, do not use an electric stove, induction cooker or electric casserole.