Put all the ingredients in a bowl or on a work surface and knead quickly with your hands to form a shortcrust pastry (do not knead too long, dough becomes burnt by hand heat and loses its binding).
Let rest in refrigerator, covered with plastic wrap, for 2 to 3 hours before processing.
Preheat oven to 160 degrees hot air.
Roll out the dough on a floured work surface and cut out the stars with a cookie cutter
Arrange the cut out cookies on a baking tray lined with baking paper and bake for about 10-12 minutes.
Decorate the cooled stars with chocolate and chopped hazelnuts.