I grew up eating fermented salted black soy beans. In the Philippines it is called tausi and sold at wet markets. They are also sold in cans and plastic pouches. My mom used to add it to sauteed bitter melon or fish. This type of fermented soy bean sauce with whole beans is no longer available here in the US although years ago I bought the canned variety from China or maybe Taiwan but couldn't find the same thing recently. Or maybe I don't know the label.