Black beans or tausi are made by fermenting and salting soybeans.
The process turns the beans black, soft, and mostly dry.
The flavor is sharp, pungent, and spicy in smell, with a taste that is salty and somewhat bitter and sweet.
(Wikipedia on Fermented Black Beans )
I’ve eaten so many delicious dishes with this ingredient, but it took me a long time to find a brand I’m really happy with.
The ones in the white plastic bag (second on the photo) were always “just not it”. Instead I would prefer the Lee-Kum-Lee ready-to-go black bean sauce (on the left). But this sauce is only good when used in things like stirfries. You can’t use it to make e.g. one of my favourites, steamed oysters.
Then I discovered these moist black beans (on the right).
They were okay. Still not brilliant, but okay. But it had this disadvantage that, once opened, you have to store them in the fridge.
But then I tried those Yang Jiang Preserved Black Beans with Ginger. And I looooove those. They are probably what all chefs are using. And they keep forever in your cupboard. You can just quickly rinse them with cold water and they are ready to use.