2. Medium-seed fermentation: the milk is heated in a microwave oven for 30 seconds, yeast and 20g sugar are added, and stirred until it is dissolved evenly. Add130g high flour to the milk yeast liquid. Stir well and ferment to twice the size.

3. Fermentation of the main dough: mix the egg liquid with 30g of sugar and salt, and add the remaining140g of high flour into the fermented culture medium seeds and into the egg liquid. Add butter and knead the dough until it comes out of the film. Fermented to twice the size.

4. Ventilate the dough, evenly divide it into three parts, let it stand and relax for 10 minutes before setting.

5. Secondary fermentation: after setting, put it into the toast box for secondary fermentation until the toast box is eight minutes full.

6. Cover the toast box, preheat the oven 190 degrees, heat the middle layer for 40 minutes, and take it out.