Ingredients
1boxvanilla cake mix,plus ingredients called for on box
1½cupsbutter,softened
6cupspowdered sugar
2tsppure vanilla extract
6tbspheavy cream
1tsppurple gel food coloring
1tspblue gel food coloring
1tspteal gel food coloring
Preparation
Preheat oven to 350 degrees F.
Line two 8-inch round cake pans with parchment paper and grease with cooking spray.
Prepare cake mix according to package instructions. Divide cake batter between prepared pans and bake according to package instructions.
Let cakes cool in pans for 10 minutes then invert onto wire racks to cool completely.
In a large bowl using a hand mixer, beat butter and half of the powdered sugar until smooth.
Add the remaining powdered sugar, vanilla, and 4 tablespoons heavy cream and beat until fluffy. If the mixture is too stiff, add more heavy cream.
Place a dab of frosting on the cake plate to keep the cake in place and place parchment strips on each side of the cake plate.
Place down first cake and top with frosting then top with second cake and frost with a thin crumb coat of frosting.
Divide the remaining frosting into three small bowls and stir one shade of gel food coloring into each bowl of frosting.
Place each color of frosting into its own piping bag fitted with a large round piping tip.
Starting at the top of one side of the cake, pipe a small circle of purple frosting.
Directly underneath the purple frosting circle, pipe a small circle of blue frosting, following by a circle of teal frosting underneath.
Continue in a vertical line in the same order of colors until you run out of space on the cake.
Using an offset spatula, smear each circle of frosting horizontally across the side of the cake about 1 inch.
Repeats steps, slightly overlapping the circles of frosting with the smeared frosting to create a mermaid-scale effect until you run out of space on the side of the cake.
Repeat the same circle and smear technique with the frosting on top of the cake but in concentric circles this time.
