1. Figure 1-2 Wash, steam and peel the purple potato, then mash it properly and put it in water for later use.

2. Figure 3-4 Prepare a clean basin, put it on the powder sieve, pour the purple potato paste into the powder sieve, and rub it repeatedly in the powder sieve and add a little water to wash the purple potato until the purple potato comes out of the stem. After all sieving, put clean gauze into a clean basin (Figure 4) and add a proper amount of sieved purple potato water.

3. Figure 5-6 Tighten the gauze mouth, slowly wring out the purple potato water (Figure 5), wring out the water as much as possible, and then pour it out for later use.

4. Figure 7-9 Take a clean pot, pour the purple sweet potato paste and fine sugar into it, turn the fire to medium fire, stir the spatula from time to time to prevent the pot from sticking, add salad oil in the middle, continue stirring until the water content is 8 minutes, turn off the fire, cool, stick it in a sealed bag and put it in the refrigerator for later use.