Mix honey, eggs, sugar, cinnamon, gingerbread spice and grated lemon zest in a bowl. Dissolve the potash and deer horn salt separately in 1 tablespoon of water (important!) And then add to the batter together with the kirsch. Add the flour and knead everything well.
Shape the dough into walnut-sized balls and place them on a baking sheet lined with baking paper. Make a small hollow in the top of the balls and press in a hazelnut-sized portion of marzipan.
Bake at 180 ° C (top / bottom heat, preheated) for 12-15 minutes. Let it cool down and then cover it all around with the dissolved couverture. Let the couverture dry and then store the biscuits in a tin can.