The answer is cooked, black beans in vinegar will have some water if boiled wrongly, which will make the concentration of vinegar become, the flavor will not be so good. From the point of view of shelf life is not recommended to cook.

Fried black beans have to pay attention to, compared to boiled black beans, fried black beans are much better, because the black itself has water, after frying the water will evaporate, so that the very tease become more fragrant.