Prepare and bake cupcakes according to package directions, adding 2 teaspoons root beer concentrate when mixing batter. Remove to wire racks to cool completely.
In a small bowl, mix whipped topping and remaining root beer concentrate until blended; spread over cupcakes. Serve with ice cream.
Notes
Cowabunga Root Beer Cupcakes
I developed these cupcakes for my daughter's first birthday and transported them using dry ice. Be careful not to freeze them solid! —Mindy Carswell, Walker, Michigan