Cupcakes:
2 cups flour
1 1/2 teaspoons baking powder
1/2 teaspoon baking soda
Pinch of salt
1/2 cup (1 stick) unsalted butter, softened
1 cup dark brown sugar, packed
3 large eggs
2 teaspoons vanilla extract
1 teaspoon butter flavoring
1/2 cup buttermilk
1/2 cup cream soda

Butterscotch Ganache:
11 ounces (1 package) butterscotch chips
1 cup heavy cream

Butterscotch Buttercream:
6 tablespoons unsalted butter, softened
1/4 cup butterscotch ganache (recipe above)
1 teaspoon vanilla
1 teaspoon butter flavoring
Pinch of salt
3-3 1/2 cups powdered sugar
Splash of heavy cream (as needed)