WHOLE FOODS RAINBOW CAKE RECIPES

Steps:

• Preheat oven to 350 degrees. Brush six 9-inch-round cake pans (or as many 9-inch cake pans as you have, reusing them as necessary) with shortening. Line bottom of each cake pan with parchment paper; brush again and set aside.
• In a large bowl, whisk together flour, baking powder and salt; set aside. In the bowl of an electric mixer fitted with the paddle attachment, cream together butter and sugar. Slowly add egg whites and mix until well combined. Add vanilla and mix until fully incorporated. Add flour mixture and milk in two alternating additions, beginning with the flour and ending with the milk. Mix until well combined.
• Divide batter evenly between six medium bowls. Add enough of each color of food coloring to each bowl, whisking, until desired shade is reached. Transfer each color to an individual cake pan. Transfer to oven and bake until a cake tester inserted into the center of each cake comes out clean, about 15 minutes (working in batches if necessary).
• Remove cakes from oven and transfer to a wire rack; let cool for 10 minutes. Invert cakes onto a wire rack; re-invert and let cool completely.
• Using a serrated knife, trim tops of cakes to make level. Place four strips of parchment paper around perimeter of a serving plate or lazy Susan. Place the purple layer on the cake plate. Spread a scant 1 cup buttercream filling over the first layer with a small offset spatula so it extends just beyond edges. Repeat process with blue, green, yellow, and orange layers.
• Place the remaining red layer on top, bottom-side up. Gently sweep away any loose crumbs with a pastry brush. Using an offset spatula, cover the top and sides with a thin layer of frosting (also use any of the excess frosting visible between the layers). Refrigerate until set, about 30 minutes.
• Using an offset spatula, cover cake again with remaining frosting.

Steps:

• Heat oven to 350°F. Grease and flour 2 (8-inch) round cake pans or spray with baking spray. Set aside.
• Combine flour, baking powder and 1/4 teaspoon salt in bowl; set aside.
• Beat sugar and 1 cup butter in another bowl at medium speed, scraping bowl occasionally, until creamy. Add eggs, 1 at a time, beating well after each addition. Add 1 tablespoon vanilla; mix well. Add flour mixture alternately with milk, beating at low speed after each addition, just until mixed.
• Divide batter evenly among 6 bowls with about 3/4 cup each. Tint cake batters red, orange, yellow, green, blue and purple. Spread red and orange batter into prepared pans. Bake 8-10 minutes or until toothpick inserted into center comes out clean. Cool 3 minutes; remove from pans to cooling rack. Cool completely. Meanwhile, wash pans; grease and flour pans. Repeat with remaining colors until all cake layers are baked.
• Beat 2 cups butter in medium bowl at medium speed until creamy. Gradually add powdered sugar and 1/4 teaspoon salt alternatley with whipping cream and 1 tablespoon vanilla, beating at low speed until well incorporated. Beat at medium speed until smooth and creamy. Remove 2 cups frosting; set aside. Divide remaining frosting evenly among 6 bowls with about 1/3 cup each. Tint frostings red, orange, yellow, green, blue and purple. Set aside.
• Place purple cake layer onto serving plate, bottom-side up. Frost top with 1/4 cup white frosting. Place blue cake layer over frosting; frost with 1/4 cup white frosting. Continuing adding green, yellow, orange and red layers in that order, frosting with 1/4 cup white frosting between each layer. Frost outside of cake with remaining white frosting. This layer of frosting will be thin and cake will be visible through frosting. Once frosted, refrigerate cake 30 minutes. (This is called a crumb coat and will prevent crumbs from interfering when piping rosettes.)
• Place each tinted frosting into individual resealable plastic food bag; push frosting to one corner. Cut off 1/2 inch from tip of corner. Place 18-inch-long piece of plastic food wrap onto counter surface. Pipe each color onto plastic wrap to form wide 12-inch horizontal lines (using all of frosting) that are touching.
• Gently roll frosting lines into one large log using plastic wrap. Snip tip off one end of plastic wrap. Place cut-side down into piping bag fitted with size 1M open-star tip. Pipe rainbow rosettes onto cake beginning with middle of top of cake and working out and down sides so the most vibrant colors are on top of cake.