1. Wash the sweet potatoes and purple potatoes separately, steam them in a pot, peel them, take 50 grams of each into a different bowl, add white sugar, and mash them. When hot glutinous rice balls are mashed with white sugar, the white sugar can quickly dissolve.
2. In three large bowls, pour 150 grams, 100 grams, and 100 grams of glutinous rice flour, and then add purple potato mash, sweet potato mash, and boiled sugar water. Stir separately and knead the smooth dough, put it in a large bowl, cover with a damp cloth, and let it sit for 10 minutes.
3. Knead the long strips separately, take 15 grams into a small ball, knead into small balls, and finish all the balls of the three colors. Small glutinous rice balls, not too big, easy to cook, good-looking and delicious. It is big, takes a long time to cook, and the color is easy to fade, especially after the purple sweet potato is oxidized, the color will turn black.
4. Pour an appropriate amount of water into the saucepan. After boiling, add the dumplings for about 1 minute. Stir evenly with a spoon to prevent sticking to the bottom of the saucepan.
5. The cooked glutinous rice balls will float on the surface, round and round, with more beautiful colors, which is a feast for taste buds and vision. You can also add a little white sugar when cooking the glutinous rice balls, so that even the soup will be delicious, with a slight sweet taste.