1. First, add 230g of high-gluten flour, 70g of low-gluten flour, 4g of salt, 30g of sugar and 4g of Angel yeast into the basin, mix the powdery substances evenly with a spatula, and then slowly pour in clear water while stirring (the water amount is about 180g, depending on the water absorption of the flour).

2. Knead the dough into a smooth dough. After kneading, add 30g of butter softened at room temperature to the dough, and then knead the dough until it is completely expanded, that is, you can pull out the glove film (kneading the dough by hand takes time, lasting about 1 hour, and this process requires patience).

3. The kneaded dough does not need to be fermented for the time being. Roll it directly into a slightly thick dough, then cover it with plastic wrap and put it in the refrigerator for 20 minutes to cool down. At this time, prepare 150g softened butter (special for ordinary butter or commendable bread), wrap it with oil paper, and roll it into butter slices with a width of 20cm 16cm.

4. Then, take out the refrigerated dough sheet and roll it into a dough sheet with a length of 35cm and a width of 22cm. Then, put the butter block vertically in the middle of the dough piece, tear off the oil paper, fold the blanks on both sides of the dough piece in half, wrap the butter block, don't let air stay in it, and then press the edge tightly. Then, roll them vertically into rectangular pieces with a rolling pin, and then fold them in the middle to form a four-sided piece.

5. Then roll it into dough in the same way, fold it in half, wrap it in a fresh-keeping bag and refrigerate it for 30 minutes to prevent butter from melting and dough from fermenting. Take out the dough sheet in 30 minutes, roll it into a dough sheet with a width of 20cm and a thickness of about 5cm, and then cut it into an isosceles triangle with a bottom of 10cm and a height of 20cm with a scraper.

6. After cutting, pull up the two bottom corners of the triangle, gently stretch it, then roll it up from the bottom, with the sharp corners facing down, and put it in a baking tray covered with oil paper.

8. Let it ferment at room temperature for about 2 hours until it becomes twice as big as it is now. Finally, brush a layer of egg liquid and put it in the oven to start baking.

9. Heat the oven to 200 degrees ahead of schedule, put the baking tray in the middle layer, and bake at 180 degrees for 20 minutes.