These are NOT the type of black beans you can eat out of a can like one does with Latino-style frijoles negros in the States. These are way too salty for that!
In Philippine cuisine, tausi are used primarily for flavoring — you lightly mash them with a fork in a way such that the skin of each bean breaks and the flavor seeps out into the dish it’s added to.
And it’s not just the flavored saltiness that they add to a dish. The way the beans were fermented gives off a distinct aroma as well.
Tausi is frequently added to Chinese-influenced fish and tofu dishes.
How exactly do you use them?
If you buy tausi in a can like this, drain the beans of the liquid and rinse with fresh water. Then add some to a dish. Rarely would you use the whole can! You can keep the remainder in a covered container in the fridge for later use.
Often, you can also find a dried version of these black beans in Asian supermarkets. It usually has Chinese characters on the packaging. For those dried beans, you’ll have to rehydrate them first by soaking in warm water.