Cream butter and sugar. Stir in eggs, lemon zest and salt. Mix flour, ground almonds and speculoos spice and add to the fat mass. Dissolve the salt of the deer horn in 1-2 teaspoons of water, also add to the bowl and knead everything into a smooth dough.
Cover and leave to cool for approx. 1 hour. Roll out the dough on a floured work surface 3-4 mm thin. Sprinkle with half of the flaked almonds and roll the dough again. Different figures, e.g.
Cut out fir trees, stars, hearts, angels, etc. Place 1/4 of the figures with the almond side down on a baking tray lined with baking paper. Bake in the preheated oven (electric cooker: 200 °C/ gas: level 3) for about 12 minutes.
Knead the rest of the dough together, roll out on the remaining almonds and also cut out. Pack cooled cookies in tins and store in a cool place. Spiced biscuits can be kept for about 4 weeks.
Results in about 90 cookies.