For the irresistible, melt the chocolate in a bain-marie over low heat. Cream the margarine with the powdered sugar, stir in the chocolate and hazelnuts and mix everything into a firmer dough.
Then let it rest for 1 hour. Form small balls from the dough and place on a baking tray lined with baking paper. Bake in the preheated oven at 150°C for about 40 minutes. Allow the biscuits to cool briefly, remove from the tray and allow to cool completely.