Makes 12 servings
This cake starts blooming when smashed sugar is pressed into the colorful frosted design.
1 Trim the top of the cake level (see On the Level). Cut the cake in half crosswise to make 2 smaller rectangular cakes. Place 1 cake on a cardboard cut to fit, trimmed side up. Spread some vanilla frosting on top of the cake. Place the other cake on top, trimmed side down, pressing it into the frosting. Spread a thin crumb coating of frosting over the cake, filling in any gaps, and smooth (see Got Crumbs?). Place the cake in the freezer until set, about 30 minutes.
2 Divide the remaining vanilla frosting evenly among 4 bowls. Tint each bowl a different color with the food coloring: pink (with the red), orange (with the red and yellow), yellow, and bright green (with the yellow and green). Spoon each color into a separate freezer-weight ziplock bag. Press out the excess air and seal the bags.
3 Line a cookie sheet with wax paper. Place the decorating sugar in a large bowl. Place the chilled cake on the cookie sheet. Download the template from http://www.hmhbooks.com/cupcakes/templates/cmd/flower.pdf and print at 200 percent. Using a toothpick, follow the template to score overlapping flower shapes in the frosting all over the cake. Snip a small (⅛-inch) corner from the 4 bags with the tinted frostings. Working on one side of the cake at a time, pipe the outline of each flower with the desired color of frosting—pink, yellow, or orange. Fill in the outlines with the frosting. Pipe the open areas with the green frosting.
4 Gently press handfuls of the sugar into the frosted side of the cake to cover (see Smashed Sugar). Brush any excess sugar from the cake. Pipe another side of the cake, fill in the outlines, and press on the sugar. Continue until all 4 sides and the top of the cake are completely covered.
5 Using an offset spatula, gently press the sugar into the frosting to smooth. Transfer the cake to a serving platter.
6 Press 3 green pearl candies into the center of each of the sugared flowers. Pipe 3 dots of green frosting near the candies, pulling up and away as you release the bag to form a tiny point.