Beat the fat, sugar, vanilla sugar and salt for a few minutes with a mixer until very fluffy. Beat in the eggs well.
Stir in flour, baking powder and baking soda briefly – just until a smooth batter forms. Fold in two-thirds of the chocolate.
Chill the dough for at least one hour.
Form balls of 2-3 centimeters from the dough, place them on a baking tray lined with baking paper, sprinkle with the remaining chocolate and flatten slightly.
Bake at about 180 °C for about 12-15 minutes until golden brown. (CAUTION: Do not let them get dark, otherwise the cookies will dry out).