1. Knead the materials other than butter to form a ball, add butter and continue kneading until smooth and filmy.
2. Put the dough in the container, cover with fresh-keeping film, and ferment in the warm place (28 ℃) to twice the size.
3. Divide and roll, cover with plastic wrap and relax for 15 minutes.
4. Roll it twice and put it into the toast mold.
5. Put it in a warm place (at 38 ℃) and ferment until it is 8 points full.
6. Close the cover 165 ° for 40 minutes.