Mix flour, yeast, sugar, salt in bread machine. Mix dry ingredient well

Add egg one at a time. Knead around 10 min until smooth dough is formed.

Add cold butter in small pieces portionwise. Knead for another 20 minutes. Check if the dough can stretch to thin film.

Transfer the dough into a bowl. Cover with plastic wrap, 1st proof at around 20C for 1 hr.

Knock air out from the dough. Knead well and do 2nd proof in the fridge overnight

Take the chill dough, knead well and cut into 3 portions. Roll the dough by hand in circular motion. Line 3 doughs in the baking mold

Proof at room temperature for 1 hr. Bake at 170C for 25 minutes.