2. Add some oil to the pot, put a few pieces of rock sugar to boil, and the boiled sugar turns red. Add appropriate amount of boiling water and stir evenly, so that the sugar color is cooked. Pour the sugar color into a small bowl for later use, add oil to another pot, add onion and ginger to stir-fry the fragrance, and then add pepper, star anise, Amomum tsao-ko, fragrant leaves, cinnamon and clove to stir-fry the fragrance again, plus some light soy sauce and soy sauce. Put the pig's trotters in the pressure cooker, then pour the boiled soup in, turn on the low heat and press for 30 minutes, and then the pot can be cooked when the time is up.