For the ice wine cookies, knead cold butter, flour, and half of the ice wine into a dough using a food processor for 5 minutes. Add the rest of the ice wine in small amounts, so that the dough is workable like any shortbread.
Let the dough rest in the refrigerator for 1 hour. Preheat oven to 180 degrees top/bottom heat. Knead shortcrust pastry, roll out on flour and cut out circles with a round cookie cutter or glass.
Put a little jam in the center of each circle, fold circles into half circles and press seams tight. Bake on a baking sheet lined with parchment paper until light, about 12 to 15 minutes.
Mix powdered sugar with vanilla sugar and turn the finished, still warm ice wine cookies in it.