Knead flour, cocoa, butter, sugar, baking powder, eggs and liqueur with the dough hooks of the hand mixer to a smooth dough. Knead in 100 g chocolate drops. Form about 48 balls from the dough and place them on 2 baking trays lined with baking paper.
Press the balls slightly flat (approx. 5 cm Ø) and spread the remaining chocolate droplets on top. Bake the trays one after the other in a preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/ gas: level 3) for approx. 7 minutes.
Remove and let it cool down on a cake rack.