Preheat oven to 350 degrees F. Coat 6-cup strawberry cake pan and 8-inch-round layer-cake pan with nonstick vegetable-oil cooking spray.
Prepare cake mix following package directions, substituting 1/2 cup juice concentrate for 1/2 cup of the water called for on package. Add the grenadine or food coloring. Pour 2-1/2 cups cake batter into prepared strawberry pan and remaining batter into prepared 8-inch pan.
Bake strawberry-shaped cake in preheated 350 degree F oven for 30 to 40 minutes, and round cake for 25 to 30 minutes or until a wooden pick inserted in centers comes out clean. Cool cakes in pans on wire racks 10 minutes. Invert cakes onto racks to cool. Cool strawberry-shaped cake, top-side down, to avoid cracking. Trim cake bottom so it sits level.
Tint 1/2 cup frosting green. Tint remaining frosting red. Use green to frost leafy top and red for the berry. Garnish with blanched sliced almonds. Wrap cake layer and freeze for up to 6 months. Makes 12 servings.