I. Dough A

1. Mix the flour, salt, and sugar together.
2. Boil water to 100°C, then slowly pour it into the flour mixture while stirring quickly.
3. The dough will thicken and the temperature is about 68°C; at this point it is “cooked” using the Tangzhong method.
4. Spread the dough on a tray, cover, and refrigerate at –1°C for about 6 hours or overnight.

II. Dough B

1. Add water, fresh milk, egg, yoghurt, and unsalted butter to a large bowl and mix well.
2. In another bowl, mix bread flour, yeast, sugar, salt, and S500.
3. Knead the dough: combine all ingredients until smooth, elastic, and no longer sticky.
   The dough temperature after kneading should be about 24°C - 26°C.
4. Add the chilled Dough A and mix gently until well combined.
5. Let the dough rise at room temperature (26–28°C) for 60–90 minutes, until it doubles in size.
6. Divide into portions as desired, shape into rounds, cover with a damp cloth, and let rest for about 15–20 minutes.
7. Roll the dough lightly lengthwise, optionally add unsalted butter (or salted butter) inside, fold and shape. Place on a baking tray, leaving space for the dough to double again.
8. Bake at 175–180 °C for 15–20 minutes.
9. Let the bread cool completely, optionally brush with melted butter, sprinkle with salt, etc.