1. First, prepare a proper amount of Ma Tofu, clear water, ginger slices, onion slices and salt, then put Ma Tofu in a bowl, add a proper amount of clear water, add ginger slices and onion slices and stir well.

2. Secondly, add a proper amount of salt, stir evenly again, seal the bowl with plastic wrap after stirring evenly, and put it in a warm place to let it ferment naturally.

3. The final fermentation time is 2 to 3 days. During the fermentation, it can be stirred once a day to promote the fermentation. After the fermentation is completed, it can be taken out and eaten.