First, put 30 kg of cold water into 5 kg of douchi, boil it with strong fire, simmer it for 45 minutes, then filter out the douchi juice. After cooling, add 4 liang soda ash, 2 liang alum, 0.5 kg of mushrooms, 10 kg of winter bamboo shoots, 2 kg of salt, half a catty of highly maotai-flavor liquor and 3 kg of bean curd, and soak it in a sealed way for about 22 days, stirring it once every two days. Second, pay attention to the brine can not be stained with oil, pay attention to hygiene, so that it is always in a state of fermentation. After continuous use for two months, add the main ingredients once. Alum and alkali should not be added together with the third brine. Pay attention to the season when soaking tofu, soak for 5 hours in spring and autumn, 2 hours in summer and 8 hours in winter. When frying, the vegetable oil should be more than 2 kg, so it needs to be fried slowly and thoroughly. Pay attention to the characteristics of softness outside and rigidity inside.