For the meringue crescents, crumble the flour with the butter and quickly knead with all the other ingredients to form a smooth dough. Wrap the dough in cling film and leave to rest in the refrigerator for about 1 hour.
In the meantime, beat egg whites with salt and as soon as the egg whites become a little firmer, gradually beat in the powdered sugar. Beat until firm and add the lemon juice.
Roll out the dough into a rectangle on a floured work surface (approx. 40×30 cm) and place the whole rolled-out piece of dough on a baking tray lined with baking paper.
Spread the snow mixture evenly on the dough and bake in a preheated oven at 160°C for about 20 minutes.
Allow to cool slightly and then cut out half moons with a cookie cutter. Let them dry well overnight.
Stick two meringue crescents together with jam.