Simmer the butterscotch beer or cream soda in a large pot over medium heat until it reduces to ½ cup. Let it cool until slightly warm.
Preheat the oven to 350°F and line cupcake pans with liners.
In a medium bowl, whisk together the flour, baking powder, baking soda, and salt. Set aside.
In a large bowl, cream the butter, brown sugar, and white sugar until fluffy. Add the eggs, vanilla extract, and butter extract, mixing until pale in color.
Stir in the butterbeer reduction and melted butterscotch chips. Gradually add the dry ingredients and buttermilk, mixing until smooth.
Divide the batter into cupcake liners and bake for 14-18 minutes. Let them cool completely.