Line 2 baking trays with baking paper. (If necessary, put the nuts on a tea towel and rub off the salt.) Chop the nuts coarsely. Cream butter, whole sugar, vanillin sugar and 1 pinch of salt. Stir in egg. Mix flour, baking powder and cocoa and stir in briefly. Fold in nuts and chocolate drops
Using 2 teaspoons, place approx. 20 piles of dough on each tray with sufficient space between them and press them slightly flatter. Bake in the preheated oven (electric cooker: 200 °C/circulating air: 175 °C/gas: level 3) for approx. 12 minutes. Let them cool down
Coarsely chop the couverture, melt it in a hot water bath with plate-grease. Dip about 2/3 of the biscuits halfway briefly into it. Leave to dry