Required.

Ingredients to prepare: 1000g of beans, appropriate amount of water

Step 1: Prepare 2 pounds of beans.

Step 2: Pick and wash the beans.

Step 3: Put the washed beans into a pot of boiling water and cook for 5 minutes.

Step 4: Rinse with running water.

Step 5: Put it outdoors and expose it to the sun for 2 days.

Step 6: Weigh it. 2 pounds is exactly 2 taels.