Black beans generally have the effect of tonifying the kidneys and benefiting the essence. Generally speaking, they should be steamed with a little salt, or soaked in salt water and then steamed or fried, which is more tonifying to the kidneys. The ancient people said that black beans have nine steaming and nine sunshine method, black beans steamed and then sunshine, so the process is carried out nine times round trip, the best kidney tonic power. The black beans are usually used with some kidney tonifying herbs, such as Dihuang, He Shou Wu and so on, such as raw Dihuang, itself is dry and cold, dry and cold, after the black beans piece of concoction, after nine steaming and nine sunshine, will become sweet and warm, tonifying the kidney, filling essence of cooked Dihuang.