Sift strong flour and weak flour on the work surface, then add cold butter and chop it with a scraper until butter pieces are about 1cm in size.

Dissolve salt in ice water and gradually mix it into the flour mixture.

Refrigerate the dough to rest.

Roll out the rested dough into a rectangle, fold it into thirds, and repeat this process three times.

Roll out the dough to a thickness of 0.3cm, sprinkle powdered sugar and cocoa powder evenly over the surface.

Roll the dough tightly and cut into 2.5cm thick pieces.

Dust the work surface with sugar and flatten each piece with a rolling pin.