Preheat oven to 180°C/325°F and line a cookie sheet with baking parchment.

Place marzipan, eggwhite, almonds, vanilla powder and baking powder in a food processor and process to a dough. Roll into a ball and divide into small portions. Roll each portions into a roll and flatten slightly into a crescent-like shape.

Whisk the egg yolk until smooth, then brush each crescent and sprinkle some of the almond flakes on top. Place onto the cookie sheet and bake on the middle rack for about 15 minutes. Take out and leave to cool.

In the meantime melt the chocolate over a double boiler then dip both crescent sides into the chocolate and leave to dry.