Pass the icing sugar through a fine sieve. Beat the eggs, vanilla sugar and salt with the whisk of the hand mixer until thick and creamy white. Add icing sugar by the spoonful and stir in. Sift the flour over it, add aniseed and kirsch and knead.
Sprinkle 1 1/2 tablespoons of aniseed seeds on each of two baking trays lined with baking paper. Roll out the dough on a well floured work surface to a thickness of about 0.5 cm. Cut out circles (approx. 3 cm Ø) and droplets (approx. 4.5 cm long).
Place the cookies on the baking trays and cover with a tea towel. Let them rest overnight at room temperature. Bake in the preheated oven (electric cooker: 150 °C/ convection oven: 125 °C/ gas: level 1) for approx. 20 minutes. Remove from the oven, place on a cake rack and allow to cool. Store cool and dry in tins