Purple potatoes are washed and peeled, sliced on a pan and steamed and allowed to cool.
Take glutinous rice flour, mix half of the purple potato puree, and evenly squeeze
Add the light milk and slowly knead it into a slightly soft dough (so hard stuffing is easy to crack)
Take a small dose, wrap it in the bean paste and slowly push it into a round shape (just like a dumpling)
On the steamer, turn the water to a small fire and steam for 10 minutes.
After steaming, immediately take out the coconut on the roll.