1. All the ingredients except butter, put all the ingredients into the mixing bucket of the chef's machine, start the program, knead into a smooth dough, add butter after 12 minutes, start a program again, check the dough, and the film can be pulled out.
2. Ferment in a warm place to 2 times the size.
3. Divide evenly into 9 parts. Cover with plastic wrap and let it stand for 10 minutes.
4. Take out one, roll it into thin slices, and put in a bean paste filling.
5. Wrap it up for import, turn it over and press it flat.
6. Divide into 8 portions.
7. Pinch each one.
8. Brush the center with egg wash and sprinkle with black sesame seeds.
9. Ferment to twice the size, put it in the preheated oven, and bake at 180 degrees for 18 minutes.
10. Cool and dense after being out of the oven.
