Mix butter, vanillin sugar and 50 g icing sugar with the whisk of the hand mixer until creamy. First stir in egg, then flour. Pour the dough into a piping bag with a star-shaped spout and squirt 10 circles (5-6 cm Ø) each onto 2 baking trays lined with baking paper. Put in a cool place for about 30 minutes. Bake trays one after the other in a preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/ gas: level 3) for 8-10 minutes.
Remove the cookies and let them cool down on a cake rack. Sieve 50 g icing sugar into a bowl. Add egg liqueur and mix to a smooth glaze. Spread the icing on the curls, then decorate with some gold leaf. Leave to dry for about 30 minutes.
waiting time approx. 1 1/2 hours