Step 1Sift flour with baking powder and salt. Cream shortening on high speed 1 minute in separate bowl. Add sugar gradually, creaming on medium-high speed until light and fluffy, 2 minutes. Add egg whites 1 at a time, beating well after each addition. Add flour mixture alternately with milk, beating on medium speed until smooth, 2 to 3 minutes. Add lemon extract.
Step 2Pour half batter into greased 9-inch cake pan. Add red food coloring to remaining batter and pour into another greased 9-inch cake pan. Bake at 375 degrees until cake springs back when lightly touched in center, 20 to 25 minutes.
Step 3Let cakes stand 5 minutes in pans, then turn cakes out on racks. When cool, split cake layers into halves crosswise. Spread jam/jelly on top surface of 1 white and 2 pink layers. Stack together, alternating layers, starting with pink and ending with white. Frost top and sides with Jelly Icing.
Step 1Melt jelly in saucepan over low heat, about 2 minutes.
Step 2Add salt to egg white and beat on high until stiff, 2 minutes. Pour melted jelly over beaten egg white and beat on high 8 to 10 minutes, or until frosting is of spreading consistency.