How to Bake a Popcorn-Shaped Birthday Cake
- 1). Prepare and bake 5 cakes using your favorite cake mix or recipe. Use 8-inch by 8-inch square cake pans to bake the cakes. Allow the cakes to cool completely. Remove the cakes from the pans.
- 2). Level the tops of all 5 cakes. Place a 10-inch by 2-inch board on either side of the cake. Lay the boards on their side so that the 10-inch sides run the length of the cake and the 2-inch side is the height of the cake. Place a serrated-knife blade on top of the boards so that the blade is resting flatly on both boards. Use a sawing motion to cut across the cake, keeping the blade flat on the boards as you go. Discard the cut-off section. Dust away any crumbs on the cakes.
- 3). Place a cake on your serving platter or cardboard cake round. Place 4 pieces of 10-inch by 3-inch waxed paper under the 4 edges of the cake. This keeps frosting from getting on the serving platter.
- 4). Apply a layer of white frosting to the top of the first cake using an offset spatula. Apply the second cake on top of the first. Place more frosting on top of the second cake. Continue to stack the remaining cakes, adding additional frosting on top of each cake layer.
- 5). Cover the sides of the stacked cakes using additional frosting. Place the cake in the refrigerator for 20 to 30 minutes to help the frosting set. Remove the cake, and frost the entire cake with a second layer of white frosting. Remove the parchment paper from under the cake.
- 6). Cut 4 pieces of white poster board into 10-inch by 8-inch pieces. Place the pieces of poster board in front of you. Add four 1-inch wide red stripes to each of the four pieces, running lengthwise. Use red paint or red electrical tape.
- 7). Apply frosting to the back of the cardboard cutouts. Press the pieces into the sides of the cake with the striped sides out. If necessary, cut pieces of clear tape and press them against the corners of the poster board where the pieces meet.
- 8). Cut marshmallows in half using a knife or pair of kitchen shears. Use miniature marshmallows for small popcorn and large marshmallows for large popcorn. Squeeze the ends of 2 pieces of cut marshmallow together to secure them. This creates a popcorn kernel. Place marshmallow popcorn on the top of the cake. Continue to mound the marshmallows until you achieve the height you want. The number of marshmallows used depends on their size.
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