1. Ingredients: appropriate amount of flour, appropriate amount of poria, appropriate amount of raisins, appropriate amount of yeast powder, appropriate amount of baking powder, appropriate amount of sugar.

2. Crush the Poria cocos with a mixer and stir evenly with the flour, baking powder and sugar.

3. Pass the mixed flour through a sieve.

4. Pour the yeast powder into warm water, stir evenly, and let stand for 5 minutes.

5. Pour the yeast water into the mixed flour and stir evenly.

6. Pour into a container, cover with plastic wrap, and ferment for 1 hour (if the temperature is low in winter, put hot water in the pot and cover the pot to speed up the fermentation).

7. After fermentation is completed (double the amount before fermentation), sprinkle some raisins on top and steam over high heat for 10 minutes.

8. Take out and cut into appropriate sizes, and the production is completed.