350 grams unsalted butter
125 grams plain yogurt
500 grams flour
6 tablespoons sugar
3 tablespoon cinnamon
3 egg whites
50 grams ‘hagelzucker’ (sugar approximately the size of small hail stones)
1/4 teaspoon salt
In mixing bowl, cream together unsalted butter and yogurt until light and fluffy. Mix in flour. The dough will be very elastic.
Roll out half of the dough on a well floured surface to 1/4 inch thickness. Mix together the sugar and cinnamon in one small bowl. Separate the eggs into another small bowl, discarding the yolks or save for another purpose. Whisk the whites to loosen (they do not need to be stiff). Brush rolled out surface of down with egg whites and sprinkle liberally with the sugar-cinnamon mixture. Roll dough into one long snake (this is how you will get the swirl effect). Wrap in aluminum foil and chill in refrigerator for 2-3 hours. Repeat with other half of the dough.
Preheat over to 190C / 375F. Unwrap chilled dough and slice with sharp knife into 1/4 inch thick slices. Place on cookie sheet lined with silpat or onto parchment paper. Brush each cookie with a very light layer of egg white and sprinkle with a bit of one of the hagelzucker.
Bake 10-12 minutes or until golden brown at the edges. Cool on wire rack.