Ingredients
Equipment
Method
Make the cupcakes
- Heat the oven to 350°F.
- Line a standard 12-cup muffin pan with paper liners.
- Whisk the flour, baking powder, and salt together in a medium bowl.
- Beat the butter and granulated sugar in a large bowl on medium speed until light and fluffy, 2 to 3 minutes.
- Beat in the eggs one at a time, then mix in the vanilla extract.
- With the mixer on low, add the flour mixture in three additions, alternating with the sour cream and champagne in two additions; begin and end with the flour mixture, and mix just until combined.
- Divide the batter among the liners, filling each about two-thirds full.
- Bake for 18 to 22 minutes, until the tops spring back lightly and a toothpick comes out with a few moist crumbs.
- Cool the cupcakes in the pan for 5 minutes.
- Transfer the cupcakes to a wire rack and cool completely.
Make the champagne buttercream
- Simmer the champagne in a 1-quart saucepan over medium heat until reduced to about 2 tablespoons, 6 to 10 minutes.
- Transfer the reduction to a small bowl and cool completely.
- Beat the butter in a large bowl until smooth.
- Gradually beat in the confectioners' sugar on low speed until incorporated.
- Add the cooled champagne reduction and beat on medium speed until the buttercream is fluffy.
Frost the cupcakes
- Spread or pipe the buttercream over the completely cooled cupcakes.
Notes
Cool the champagne reduction completely before adding it so the buttercream stays fluffy. Refrigerate frosted cupcakes for up to 3 days; unfrosted cupcakes can be frozen. For a nonalcoholic variation, use nonalcoholic sparkling wine in place of the champagne.
