Knead a dough from the flour, sugar, butter and egg. Let rest in a foil for about 1 hour.
Preheat the oven to 200 ° (convection 180 °).
Roll out the dough ½ cm thick, cut out stars, place on the tray. Bake in the oven (center) for 8-10 minutes until light brown.
Mix the icing sugar, juice and 1 tablespoon of jam together. Brush the cookies with it. Put 1 pinch of jam in the middle of each star and pull it into the icing with a wooden stick.