Mix powdered sugar with flour. Add salt, egg yolk and apricot liqueur. Work into a dough with the grated orange peel and margarine.
Pour the batter into a piping bag with a large star nozzle. Squirt stars about 4 cm in size onto a baking sheet lined with baking foil. Bake the stars in the preheated oven on the middle rack at 180 degrees (gas: level 3) for about 12 minutes and leave to cool on a wire rack.