Amirah Kassem, cookbook author and baker behind Flour Shop's eye-catching explosive rainbow cakes, shows how to make one of her magical creations.
"When dyeing the frosting, remember to start with 1 drop food coloring," says Amirah. "Mix it in, and add more until it is as bright as you want it to be. If you don't have the exact colors, try red and blue for purple, and yellow and red for orange, for example."
Adapted from The Power Of Sprinkles by Amirah Kassem. Copyright © 2019 by Amirah Kassem. Used with permission by Abrams. All rights reserved.
- 1 ¾ cups rainbow sprinkle explosion mix, such as sprinkles, chocolate malt balls, and M&Ms
- 8 to 10 Oreos, crushed, for soil
For the cakes, preheat oven to 350˚F and position oven rack in the middle of the oven. For convection ovens, preheat to 325˚F.
Divide the undyed batter among four greased 8-inch round baking pans. Bake two cakes at a time for 20 minutes, then rotate and bake for another 10 minutes or until a toothpick inserted into the center comes out clean. Let the cakes cool in the pans for 5 to 10 minutes. (When they're warm, they're really fragile, and that's when they tend to break.) Flip them over onto a baking sheet or cooling rack and let them cool completely before frosting.
While the cakes cool, dye the frosting: For the pot, dye ⅓ of the frosting light brown. For the flowers, dye 1 cup each of the frosting purple, orange, yellow, and pink. For the leaves, dye ½ cup frosting green. You should have plenty of white frosting leftover for filling in the layers, or if you need to make more of any color.
Fill several different piping bags with piping tips and colored frostings for your flowers and leaves, so that you have them all on hand to add flowers and leaves in the pattern you like.
For the magic, make the "soil": Smash Oreos in a plastic bag with a rolling pin, or use a food processor if you have one.
Using the cooled cake layers and frosting, assemble the cake: Use a 2-inch round cookie cutter to cut the center out of every layer cake but one.
Prepare the work surface by finding a base upon which to build your cake. Use disposable round cake decorating boards or a plate, cake stand or flat platter. Make the cake stick by piping a small ring of white frosting directly on top of the cake board to fit the cake. Put the first layer of cake directly on top, then cover the top with an even layer of frosting, leaving a little room around the hole to keep the sprinkle explosion filling from sticking to the frosting. Be sure to use the same amount of frosting for each of the layers. Add the second layer of cake, making sure to line up the holes in the center of the cake layers, and frost. Repeat with the third layer cake.
Pour sprinkles down the center of the cake into the hole. Flip the last layer cake upside-down and set into place; this ensures you have a flat surface for the top of the cake.
Frost the entire outside of the cake with a thin layer of light brown frosting using a spatula or dull knife. This thin layer of frosting is called the "crumb coat," which helps everything stick. Then, frost the sides of the cake in a thicker coat of light brown frosting, leaving the top bare for the "soil" and "flowers," and frosting a thicker rim towards the top, if desired, for a planter effect.
Add the "soil": Use your hands to make a thick, fluffy border of cookie crumbs around the edge of the top of the flower pot. Be sure to leave the center of the top clear for your flowers, because frosting doesn't stick as easily to cookie crumbs.
Add the "flowers and leaves": Slowly add flowers to the top of your cake, adding a few of each color at a time, letting them just overlap the "soil." (It also helps to practice a little on parchment or waxed paper or even a plate before you begin.) Fill in any space between the flowers with green for the leaves. If your frosting starts to get too warm, which makes for droopy flowers, place it in the fridge for a minute or two.