Beat egg whites until foamy with sturdy egg beater, or at high speed of electric mixer. Then add 1 cup sugar gradually, beating only until meringue will hold up in soft peaks.
In a large bowl, stir shortening just to soften. In another bowl, sift together flour, baking powder, salt, and 2 cups sugar; sift into shortening. Add 1 1/2 cups milk and the extracts, and mix until all flour is dampened. Beat 2 minutes at a low speed of electric mixer. Add remaining milk and the meringue mixture; beat for 1 minute more.
Line the bottoms of one 10 inch square pan and two 8 inch square pans with parchment paper. Pour batter to equal depth in each pan.
Bake at 325 degrees F (165 degrees C) for about 45 minutes, or until done. Cool layers.
Trim one of the 8 inch square cakes to make a 5 inch square cake. Place the 10 inch cake on a large flat tray or plate. Frost top and sides with thin layer of Ornamental Icing. Cover top of cake smoothly with more frosting. Center 8 inch cake on top of 10 inch cake, and frost as above. Center 5 inch cake on 8 inch cake, and frost. Spread frosting over entire cake to give a flat, even base for decorating. Decorate as desired.