1. Soak the dried Pleurotus eryngii slices in clean water for 1 hour, then take them out and wash them. The soaked water is filtered to remove sediment for later use.

2. Boil the pig's trotters in boiling water for 5 minutes, remove and wash off the blood foam.

3. Put the pig's trotters into the pot, pour in the filtered water soaked in the dried Pleurotus eryngii slices and appropriate amount of water, and add the onion and ginger slices.

4. After boiling, add cooking wine and simmer for 1.5 hours, then add the soaked Pleurotus eryngii slices, fresh mushroom slices and Tricholoma, simmer for 10 minute after boiling, and add salt and chicken essence.

5. Because of the water soaked in the dried slices of Pleurotus eryngii, the soup is a little dark, but it is very fragrant and fresh, with the unique fragrance and flavor of dried Pleurotus eryngii.