Mix the cake batter according to directions and then divide it evenly into 3 bowls.
Use a few drops of food coloring to die one bowl of batter pink, one purple and one turquoise. Mix according to your color preference.
Spoon 1 teaspoon of the pink batter into each cupcake liner. Repeat the process spooning 1 teaspoon of purple and 1 teaspoon of turquoise into each cupcake liner. Repeat with all 3 colors again, alternating your placement of colors to create a marbled effect.
Bake the cupcakes according to your directions. Allow them to fully cool before icing.
Separate your frosting into 2 bowls and die one pink and one turquoise with your food coloring.
Place the pink frosting on one side of your piping bag. Add the turquoise frosting to the other side of the same piping bag, doing your best not to mix the colors.
Pipe your frosting onto your cupcakes. Top with sprinkles and the cupcake toppers of your choosing. Enjoy!