Mix the butter with the powdered sugar, marzipan, vanilla sugar and lemon zest. Sift the flour over the butter mixture and knead in. Shape the dough into rolls of the same size (approx. 5 cm in diameter), wrap in aluminum foil and leave to rest in the refrigerator overnight.
Preheat the oven to 190 ° C (top / bottom heat).
Brush the pastry sticks with the beaten egg yolk and roll in the sugar. Cut off 1/2 cm thick slices, place on a baking sheet lined with baking paper and bake for 10-15 minutes.