1. Prepare the ingredients, cut purple sweet potato into small pieces, soak in fruit wine for 30 minutes, and then dry
2. Put the butter and butter cookie mix together and mix well, then add the yogurt
3. Mix flour and yogurt evenly
4. Throw in purple sweet potato
5. After mixing, put it in the refrigerator for more than 1 hour
6. Roll out the iced dough into large pieces
7. Cover the two sides of the dough sheet in the middle to make it into three layers, and then roll out a large sheet. Repeat this step 3 times
8. Roll the dough folded three times into a 1.5cm thick sheet
9. Press out the cookie dough with a cookie mold
10. Sweep the egg liquid
11. The electric oven is heated to 170 degrees, lowered to 180 degrees, and bake for 30 minutes
12. Take out and let cool and ready to eat
