Hungarian Christmas Cookies Ingredients: 6 cups Flour 2 cups Unsalted Butter, softened 2 cups Sour Cream ½ cup Milk 1 pkg. Dry Yeast 1 tsp. Salt 4 Eggs, separated Filling: 3 pkg. Pitted Prunes To taste Sugar Procedure: Day 1: . Warm milk, add yeast and let stand for 5 minutes . Mix egg yolk, sour cream and butter together . Add yeast and milk then flour and mix to a dough . Wrap dough in wet towel and leave in the refrigerator overnight Day 2: . Preheat oven to 350 ? C . Boil pitted prunes and sugar to together until the prunes have broken down into a paste. Let cool . Roll dough mixture on a floured and sugared surface to ?" thick . Cut into approximately 3" squares and add a teaspoon of prune filling to the centre of each square . Fold one corner over the centre and roll to opposite corner. (Leave ends open) . Brush with the egg white and a splash of milk . Bake until golden brown