for the cupcakes
1/2 cup unsalted butter, softened
1 cup sugar
1 teaspoon vanilla extract
1 3/4 cups flour
1/2 teaspoon baking soda
1/4 teaspoon baking powder
1/4 teaspoon salt
1/2 cup sour cream
1/2 cup sparkling wine
for the frosting
3 – 3 1/2 cups powdered sugar
1 cup unsalted butter, softened
1/2 teaspoon vanilla extract
3 – 4 tablespoons sparkling wine
For the cupcakes: Preheat oven to 350F. Line cupcake pan with paper liners.
In a large bowl, beat sugar and butter together until light and fluffy. Add eggs, one at a time, mixing after adding each one. Mix in vanilla. In a medium bowl, combine flour with baking soda, baking powder, and salt. Set aside. In a small bowl, carefully mix sour cream and sparkling wine together. Alternate adding flour and sparkling wine mixtures to large bowl, beginning and ending with flour. Add 1/4 cup of batter to each cupcake liner (they should be a little over half full). Bake for 18-20 minutes, until a toothpick inserted in the middle comes out clean. Let cool completely.
For the frosting: beat powdered sugar and butter together on medium for 2 minutes, until light. Add vanilla and sparkling wine, then beat for another minute. Pipe onto cooled cupcakes and garnish as desired.