Put 90 g (approx. 45 pieces) walnut halves aside. Grind the remaining walnuts finely. Knead with butter in flakes, sugar, egg, salt, flour and starch to a smooth dough. Wrap in foil and chill for about 30 minutes. Then roll out on a lightly floured work surface and cut out about 90 flowers.
Place on baking trays lined with baking paper. Bake in a preheated oven (electric cooker: 175 °C/ convection oven: 150 °C/ gas: level 2) for approx. 12 minutes. Let them cool down. Warm up the jam. Spread half of the biscuits with the jam. Leave 1 tablespoon. Place a second cookie on each. Decorate with sugar writing in a grid pattern. Spread the rest of the jam on the middle of the cookie blossoms and place 1 walnut half on each.
Spread half of the biscuits with the jam. Leave 1 tablespoon. Place a second cookie on each. Decorate with sugar writing in a grid pattern. Spread the rest of the jam on the middle of the cookie blossoms and place 1 walnut half on each. Dust delicately with icing sugar