Preheat oven (electric cooker: 200 °C/circulating air: 175 °C/gas: see manufacturer). Coarsely chop peanuts. Mix flour, cocoa and baking powder. Cream butter, sugar, vanilla sugar and salt with the whisk of the mixer until the sugar is dissolved.
Stir in the egg. Stir in flour mixture briefly. Fold chocolate drops and nuts into the dough.
Using a tablespoon, place 6 piles of dough on each of two baking trays lined with baking paper. Press slightly flat to make round biscuits (approx. 7 cm Ø each).
Bake the biscuits sheet by sheet in a hot oven for about 12 minutes. Let them cool down on the baking paper and only then remove them.