Line a baking tray with baking paper. Coarsely chop the nuts and chocolate separately. Melt 100 g chocolate in a hot water bath, let it cool down a little. Preheat the oven (electric cooker: 175°C/circulating air: 150°C/gas: level 2).
Melt the butter. Add sugar, egg, vanilla sugar and 1 pinch of salt and stir in with the whisk of the mixer. Mix flour and baking powder and stir in. Fold in the melted chocolate.
Fold in chopped chocolate and hazelnuts.
Cut about 80 "Mikado" sticks in half. Place about 5 pastry blobs on the baking tray with a large gap between them. Put 4 "Mikado Sticks" almost vertically on each side of a blob of dough (they lie down during baking) as "legs" in the dough.
Bake in the oven for 15-18 minutes.
Bake about 15 more cookie spiders from the remaining dough and "Mikado" sticks. Let them cool down.
For the icing, mix icing sugar and 1 tablespoon of water until smooth. Pour into the disposable piping bag or freezer bag. Cut off a very small tip. Spray "eyes" on each spider and press the sugar pearls lightly.
Spray a cross on the back of some spiders with the rest of the cast. Leave to dry.