I used a new 10-inch terracotta saucer as a planter for my cactus cakes. You can find them at most home improvement stores in the gardening section. If you also choose to use a terracotta dish, be sure to wash it thoroughly and allow it to dry overnight before using.
Make the cakes: Preheat the oven to 350°F. Spray a 6 cavity mini ball pan (cavity size 3.5 inches each) with flour-based baking spray
Mix flour, sugar, baking powder and salt in a large bowl. Add butter and milk; mix on low speed with an electric mixer. Add vanilla and increase speed to medium, beat for two minutes.
Reduce speed to medium-low and gradually add the egg whites in two additions. Beat at medium speed for 2 minutes. Pour batter into the cavities of the prepared pan and smooth the surface lightly with a rubber spatula.
Bake the cakes for 20-30 minutes, or until the tops are golden brown and a toothpick tester comes out clean. Let the cakes cool for 10 minutes in the pan before turning them out onto a wire rack to cool completely. Level the tops of the cakes with a serrated knife.
Make the buttercream: Combine the butter and confectioners’ sugar in a large bowl. Beat on medium speed until combined. Add the lemon extract and mix well. Add milk or cream 1 tablespoon at a time to thin the mixture to piping consistency. Beat at high speed for 3 minutes or until light and fluffy. Remove 1 cup of frosting and transfer to a disposable piping bag with a 1/2-inch hole snipped in the end.
Divide the remaining buttercream in half. Tint one portion with the juniper green food color and a little of the yellow gel food color until a deep green cactus color is achieved. Divide green frosting in two portions, and transfer one portion to a piping bag fitted with Ateco piping tip #825 (7/16” open star). Transfer the other portion to a piping bag fitted with Wilton piping tip #32 (open star).
Tint the remaining portion of buttercream with yellow food color, and a little juniper green food color until a yellow-green color is achieved. (You should use more yellow food color than green.) Transfer the frosting to a piping bag fitted with a Wilton tip #125 (large petal).
Pipe a thin coat of the untinted frosting onto three of the cooled half ball cakes. Sandwich each with another half ball cake. Chill cakes until firm, about 10 minutes.
Using some of the remaining buttercream, place four dots of frosting in the saucer or planter dish. Line the saucer with waxed paper (the frosting will help hold the paper in place). Add another dot of frosting and place a ball cake on top of the dot. Surround the cake with the cookie crumbs, filling the saucer.
Cover the ball with frosting stars using the green frosting fitted with the #825 Ateco tip. Place a second ball cake into the planter, spacing it about 2 inches from the first. Cover the second ball with frosting stars using the green frosting bag fitted with the #32 Wilton tip. Cut the third ball cake in half. Use a 2.5-inch tear-shaped cookie cutter to cut a piece from one of the halves. Place a 4-inch long wooden dowel or skewer into the pointed end. Insert the wooden dowel into the top and slightly off-center into the first cake (piped with #825 tip). Cover with green frosting stars with the bag fitted with the #825 tip.
Pipe overlapping petals on the last ball cake half using the yellow-green frosting fitted with the petal tip. Keep piping petals until a large cabbage shape is achieved. (See blog post for further petal-piping instruction). Refrigerate until firm. When the cake is firm, transfer to the planter dish.
Make the cactus spines: Line a baking pan with parchment paper. Heat the white candy wafers in the microwave at 30 second intervals until the candy can be stirred smooth. Transfer the candy to a disposable piping bag snip a small hole in the end. Pipe thin lines of candy onto the parchment paper; let dry until firm. When the candy is firm, use a knife or bench scraper to cut the candy into 1-inch pieces for the spines. Press two spines into each of the large stars piped onto the first cactus cake (#825). Press one spine into each piped star on the second cake (#32).
Make the pink cactus flower: Roll the pink fondant to 1/4-inch thickness. Use a small 5-petal flower cutter to stamp 4 pieces from the fondant. Roll a small scrap piece of fondant into a ball. Place a skewer into the ball. Thread one of the flowers onto the skewer and brush the inside of the flower with water. Fold the petals upward to a closed position around the ball. Thread the other flowers onto the skewer, staggering them so the petals do not line up with each other. Cut the skewer to 3-4 inches using scissors, and insert into the top of the cake piece on the first cactus piped with #825.
Finish the cake by garnishing the cookie crumb ‘dirt’ with cacao nibs.
Keyword american buttercream, cactus cake, fondant