Combine flour, baking powder, and salt; add to creamed mixture alternately with milk, beginning and ending with flour mixture. Mix well after each addition. Stir in flavoring.
Beat egg whites (at room temperature) until stiff but not dry; fold into batter.
Pour batter into 2 greased and floured 9-inch round cake pans. Bake at 350° for 35 to 40 minutes or until a wooden pick inserted in center comes out clean. Cool in pans 10 minutes; remove layers from pans, and let cool completely.
Spread Orange Filling between layers; spread top and sides of cake with frosting, and sprinkle with coconut.