Preheat oven to 350°F. Spray 10 in. round pan with vegetable pan spray.
Prepare cake mixes following package instructions: divide batter into thirds. Each third will become one layer (approximately 3 2/3 cups of batter). Pour 1/3 of the batter into prepared pan.
Bake 27-30 minutes, or until cake tests done. Cool in pan 10 minutes; remove and cool completely on cooling grid.
Wash and dry cooled pan; spray with vegetable pan spray. Stir almond extract, if desired, chopped cherries and red icing color into 1/3 of the batter; pour into prepared pan.
Bake 27-30 minutes, or until cake tests done. Cool in pan 10 minutes; remove and cool completely on cooling grid.
Wash and dry cooled pan; spray with vegetable pan spray. Stir pistachios and green icing color into remaining 1/3 of the batter; pour into prepared pan.
Bake 27-30 minutes, or until cake tests done. Cool in pan 10 minutes; remove and cool completely on cooling grid.
Stack layers on serving plate, spreading icing between layers. Spatula ice cake smooth; add tip 32 buttercream swirls.