Roll pastry on floured surface to 2 20" x 15" rectangles. Trim edges evenly. With a sharp knife cut into 12 5" squares. Spoon a rounded tablepoon prune filling onto center of each square; bring 2 opposite corners over filling to overlap about 1 inch. Placwe on cookie sheets 2 inches apart. Let rise in a warm place until double in bulk, about 30 minutes. Brush with beaten egg. Place in hot oven (400�f); lower heat immediately to 350�f, then bake for 20 minutes. Warm corn syrup slightly in small saucepan; brush over pastries; bake 5 minutes more. Remove to wire rack; cool. You may substitute cherry or apple pie filling, or apricot preserves for the prune filling.