Cut the chocolate bars into small pieces. Cream butter, sugar, salt and vanilla sugar with the whisk of the hand mixer until the sugar is dissolved. Stir in the eggs one after the other. Mix flour and baking powder and stir in. Fold in about 2/3 of the chocolate pieces.
Using a tablespoon, place 6 piles of dough (1 heaped tablespoon each) on 3-4 baking trays lined with baking paper and press flat. Sprinkle the rest of the chocolate on the cookies. Bake the trays one after the other in a preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/ gas: level 3) for 10-12 minutes. Remove from the baking tray, place on a cake rack and allow to cool
15 minutes waiting time