Make icing one day in advance for more vibrant color. Prepare medium consistency buttercream icing following recipe directions. Divide icing in half; set aside one half that will not be tinted. Use red icing color to tint other half red.

Bake and cool cupcakes. Prepare batter following recipe directions. Bake and cool cupcakes in baking cups following recipe directions.

Prepare icing bags. Fill one decorating bag 1/4 full or less with white icing and another 1/4 full or less with red icing. Use scissors to cut bags 1/2 in. from end. Flatten bags slightly.

Place tip 1M in a third cut decorating bag. Place the filled icing bags in the third bag, making sure tips of smaller bags are nestled in tip 1M. Twist tops of bags together.

Ice cupcakes. Pipe a swirl on top of each cupcake. Each double-filled bag will ice 4 to 5 cupcakes.