Buy cooked pig's trotters, choose the black ones,

2. Come back and soak in cold water for half a day, scrape off the black skin, clean it, cut it open, boil it in boiling water 10 minute, take it out and wash it.

3. Boil the soup pot in cold water, add star anise 1 piece, one Amomum tsaoko, three fragrant leaves and 5.6 ginger slices, boil with strong fire, and remove the floating foam.

4. Add soybeans, turn to low heat, open it after 3 hours, and add salt when drinking.