Douchi (from Chinese 豆豉 dòuchǐ), also called hamanatto or Chinese fermented black beans, is a flavoring most popular in the cuisine of China, and is used to make black bean sauce.
Douchi is made by fermenting and salting soybeans. The process turns the beans black, soft, and mostly dry. The flavor is pungent and bacterial, although it does not compare with natto or the smellier cheeses.
Use
Douchi is especially used to flavor fish or stir-fried leafy vegetables. Unlike some other fermented soybean-based foods such as natto, miso or tempeh, douchi is only a seasoning, not meant to be consumed in large quantities.
Small packets of douchi are available wherever Chinese foods are sold.