1. All materials are ready
2. Stir all the ingredients except the purple potato mash and knead into a dough
3. One part is added with purple sweet potato mash
4. Knead into a smooth dough, cover with plastic wrap to ferment
5. Dip some powder on your finger, poke a small hole and not immediately retract
6. Roll out the two dough pieces into the same length as the toast box, and press the purple potato noodles on the white noodles
7. Roll it up and put it in a toast box, ferment to 8 minutes full, put it in the oven and bake at 200 degrees for 30 minutes.
