For the pre-dough, warm light and dark syrup lukewarm and mix with wheat and rye flour. For the fat dough mix fat, icing sugar, wheat flour, gingerbread spice and salt. Knead the pre-dough and fat dough. Stir potash and deer horn salt separately with 1 tablespoon of water each until smooth and knead into the dough one after the other. Let it rest overnight at room temperature. On a floured work surface, roll out to a thickness of approx. 3 mm into a rectangle of approx. 28x36 cm and cut into rectangles of 4x6 cm.
Place on 2 baking trays lined with baking paper. Bake one after the other in a preheated oven (electric: 200 °C/ gas: level 3) for 6-8 minutes. Take out and let cool down. Mix 5 tablespoons of water with icing sugar until smooth and coat the cakes with it. Decorate as desired with almonds, cherries and pistachios. Results in approx. 42 pieces