Finely grate the marzipan. Knead butter in flakes, icing sugar, flour and marzipan to a smooth dough. Form into a roll (approx. 4 cm Ø). Wrap in foil and chill for about 1 hour. Mix sugar and ground almonds. Whisk the egg yolk, brush the roll with it and turn it in the sugar mixture. Cut into approx. 5 mm thick slices.
Distribute on 2 baking trays lined with baking paper. Press 2 almonds each onto a biscuit. Whisk 1 egg yolk and milk. Spread the biscuits with it. Bake in the preheated oven (electric cooker: 175 °C/ convection oven: 150 °C/ gas: level 2) for about 15 minutes. Let cool and dust with icing sugar
Waiting time approx. 1 hour