Step 1

Preheat the oven to 350 degrees F. Stand the ice cream cones upright in the cups of two 12-cup muffin tins (or bake them in batches if you only have 1 tin).

Step 2

Whisk together the oil and eggs in a bowl. Add the cake mix, vanilla extract and 1 cup water and mix until no lumps remain. Divide the cake batter into 3 bowls. Tint each batter with a different color gel food coloring (pink, purple and green), adding as much as needed until the desired shade is reached.

Step 3

Fill the cones with the batter, alternating colors, until halfway full (they expand as they bake). Using a skewer in an up-and-down motion, marble the batter in each cone 2 to 3 times. Bake until a toothpick inserted in the center of a cupcake comes out clean, 14 to 16 minutes. Let cool completely.

Step 4

Meanwhile, microwave the pink, purple, blue and green melting candy wafers in 4 separate microwave-safe bowls (one color in each bowl) for 30 seconds, then stir. Continue heating for 5 to 10 seconds at a time, stirring, until completely melted and smooth.

Step 5

Pour the melted candy into mermaid tail silicone molds (2- to 3-inch tails), alternating colors. Place in the freezer for 6 to 8 minutes to set. Continue the process until you have enough mermaid tails.

Step 6

Spread the cooled cupcakes with the blue frosting. Press a mermaid tail into the center of each cupcake, about 1/4 inch into the frosting.