Blend the butter, cream cheese, sugars and egg yolk. Sift flour and baking powder and add to creamed mixture. Mix well and chill for at least 1/2 hour. Roll out like pie dough and cut into about 3" squares. Add a filling (prune,almond,apricot,etc). Put about a Tbls filling in the center of square. Loosely fold 2 opposite corners over and to the center, leaving the other two open. Bake 350º for 10-15 minutes until golden brown.
Not a NESTLÉ®-tested recipe.