Preparation of ingredients:

White dough: formula milk/milk 100g, 2g yeast, 200g flour.

Purple potato dough: purple potato paste 80g, yeast 2g, formula milk/milk 50g, flour 150g.

Production method:

1, respectively, melt the yeast with warm water, put it into 2 parts of flour, add formula milk and purple potato paste, and knead it into smooth dough.

2. Divide two portions of dough into 1/4 portions and knead them into dough.

3. Roll the white dough into a circle, wrap the purple potato dough in it, tighten it with a tiger's mouth, and put it down at the closing place (flatten the two doughs to make a purple potato roll, stack them together, roll them up and cut them).

4. A sharp knife crosses. Be careful not to let the noodles stick together, or they won't bloom.

5. Spread oiled paper or cage cloth in the pot, put it in and stir it until it is 15 times larger, boil the water for 12 minutes, and keep it stuffy for 3 minutes.