1. Drain the water from cooking the beans, add a little salt and store them in the refrigerator (or not).

2. Put the beans into a stainless steel pot with a lid and ferment in a warm place for about a week. There should be slippery mucus between the fermented beans.

3. Cut the ginger into small pieces.

4. Pour the bean cooking water into the fermented soybeans, add grated ginger, salt, and chopped pepper into the beans and mix well. This water tempeh is ready. The amount of salt used depends on the amount of beans. Because chopped pepper contains salt, the weight of salt is not specified here. Just add it and eat it to make it salty.

5. Stir evenly and the black bean sauce is ready.

6. Store the tempeh in a glass container and leave it for half a day before eating. Tempeh should not be left at room temperature for too long, as it will become sour over time. You can put it in a crisper and refrigerate it, and it can be stored for a long time.