Preheat oven to 350°F (177°C). Add cupcake liners to cupcake pans and set aside.
In a large mixing bowl, combine cake mix, champagne, eggs and oil. Mix on medium speed until fully combined.
Add 3 tablespoons of cake mixture to each liner.
Bake for 15 minutes or until a toothpick inserted into the center comes out clean. Transfer to a cooling rack and allow to come to room temperature.
While cupcakes are cooling, make the frosting by adding butter to a large mixing bowl. Mix on medium-high speed for 1 minute.
Add in powdered sugar and champagne a little at a time. Continue to mix on low speed until fully combined.
Pause to taste frosting and scrape the sides of the bowl. For a creamier frosting, add half-and-half. For a stronger champagne flavor, omit the half-and-half and add in additional champagne. Salt to taste.
Once cupcakes have cooled, decorate cupcakes with frosting and gold sprinkles.
Notes
Creamier frosting: Use half-and-half for a creamier frosting with less champagne flavor. Stronger champagne flavor frosting: Omit the half-and-half and add in additional champagne. You can mix it up until it reaches the desired consistency!