Crumble the marzipan into a bowl with your fingers. Mix in the egg white, icing sugar, flour, ground almonds, cinnamon, amaretto and a pinch of salt until you have a soft dough.

Heat the oven to 175C/fan 155C/gas 3 1/2. Cover 2 baking sheets with baking parchment. Make 25 small balls from the dough with your hands and space them out on the baking sheets. Press down on each dough ball with the back of a fork to make a groove pattern.

Brush the egg yolk glaze over the cookies. Now sprinkle with chopped almonds, if using. Bake for 12-15 minutes. Cool completely.