First of all, the main raw materials, such as Gleditsia sinensis, seed oil and Polygonum multiflorum Thunb, can be broken with a small hammer at home, and then washed with clear water. It takes more than half an hour to soak in the water, or longer.

2.

Then, don't use iron pots, stainless steel or casserole. You can add three times as much water as the raw material at a time. Boil first with high fire and simmer slowly. Pay attention to stirring when cooking, and don't stick to the pan. It usually takes more than 5 hours to cook. After cooking, filter out the dregs and set aside to cool. In summer, they can be stored in the refrigerator.