Mix and sift flour and baking powder. Cream butter or margarine, add sugar slowly, and cream until fluffy. Stir in well-beaten egg. Add sifted dry ingredients, blend well and chill. Roll ?-inch thick on lightly floured board. Cut in desired fancy shapes. Brush tops with egg white diluted with water and sprinkle with sugared cinnamon. Split the almonds and arrange 3 halves on each tart at equal distances. Bake on ungreased sheet in moderately hot oven (425 F.) 8 minutes. Yield: 10-12 dozen small tarts.