For the Schneebusserln, crumble the butter with the flour and quickly mix with the remaining dough ingredients to make a smooth shortcrust pastry. Let it rest in the refrigerator for about 1 hour.
Preheat the oven to 150ºC hot air.
In a cold, completely fat-free container, beat the egg whites with a pinch of salt until they turn white. Gradually add the sugar and continue beating until the snow is stiff and forms beautiful peaks.
Roll out the shortbread on a floured work surface and cut out small round disks. Place the cookie slices on a baking sheet lined with parchment paper.
Pour the beaten egg whites into a piping bag and pipe onto the shortbread slices. Start at the cookie, press on some of the mixture and pull the piping bag upwards until a tip forms.
Bake in the oven for about 20 minutes. Keep an eye on the baked product, it should not turn brown.
When cool, glue two snowballs together with jam.