Mix the softened butter with the sugar and salt until frothy. Knead in the flour and wrap the shortcrust pastry in foil for 2 hours in the refrigerator.
Preheat the oven to 160 ° convection. Roll out the dough on a baking sheet about 1/2 cm thick. Prick the dough several times with a fork and bake for 25-30 minutes. Cut the hot dough sheet with a sharp knife into strips of 1.7 cm and immediately turn in sugar.