Finely grate the marzipan mixture and knead with the butter, powdered sugar and flour to form a smooth dough. Form 2 rolls with a diameter of about 4 cm and wrap them in foil and put them in the fridge for about 1 hour.
Mix the sugar and ground almonds. Whisk 1 egg yolk, brush the rolling pin with it and turn in the sugar mixture. Cut into slices about 5 mm thick and place on baking sheets lined with baking paper. Press the chopped almonds onto the cookies. Whisk 1 egg yolk with the milk and brush the cookies with it. Bake in the preheated oven at 175 ° C for about 15 minutes.