For the star towers, place all the ingredients in a bowl or on a work surface and knead quickly with your hands to form a shortcrust pastry. Leave to rest for two hours in the refrigerator, covered with cling film, before processing.
Preheat the oven to 170 ºC hot air.
Roll out the dough on a work surface sprinkled with flour. Cut out stars of different sizes, place on a baking tray lined with baking paper and bake for about 12 minutes.
Stagger the individual stars and stick together with jam of your choice. Sprinkle with a sugar and cinnamon mixture.