2. Because black beans are hard as a whole, soak them in water before cooking. It can only be cooked after soaking, and it can be drunk in about half an hour. Soaking beans in advance can not only make beans heated evenly and cook faster, but also remove the astringency of black beans.

3. black bean porridge is easy to digest, which can meet the needs of human body for protein. It contains unsaturated fatty acids, which can reduce cholesterol in blood, and is rich in vitamins, melanin and lecithin, which can delay aging, reduce blood viscosity, meet the brain's demand for trace substances, and has the effects of promoting blood circulation, replenishing water, expelling wind and detoxifying.