Buttery vanilla cupcakes infused with cream soda and butterscotch, topped with a rich butterscotch buttercream—just the kind of magic worthy of any Potter fan.
Preheat oven to 350°F. Line a 12-cup muffin tin with cupcake liners.
Whisk flour, baking powder, baking soda, and salt in a bowl; set aside.
In a large bowl, beat 0.75 cup softened butter with granulated sugar and brown sugar until light and fluffy, about 2 to 3 minutes.
Beat in eggs one at a time, then mix in 2 teaspoons vanilla extract until smooth.
Add dry ingredients in 2 additions, alternating with cream soda. Mix on low just until combined; fold in 0.25 cup butterscotch sauce.
Divide batter among liners, filling each about 0.67 full. Bake 18 to 20 minutes, or until a toothpick comes out clean.
Cool cupcakes in the pan 5 minutes, then transfer to a rack to cool completely before frosting.
Make frosting: Beat 1 cup butter until creamy. Gradually add powdered sugar, then beat in heavy cream, 0.25 cup butterscotch sauce, 0.5 teaspoon vanilla, and salt until fluffy, 2 to 3 minutes.
Pipe or spread frosting onto cooled cupcakes. Drizzle with a little extra butterscotch sauce and add gold sprinkles if desired.
Notes
For the best flavor, use a thick, buttery butterscotch sauce (not thin syrup). If your frosting is too thick, add an extra splash of cream; if too thin, add a few spoonfuls of powdered sugar.