1. Preheat your oven to 350 (degree sign) and line a dozen cupcake tins with cupcake paper liners.
2. Combine the root beer and vinegar, let stand for a few minutes. Add in the sugar and oil, whisking vigorously until slightly frothy.
3. Combine amaretto with vanilla, and gently introduce the flour, along with the baking powder, baking soda, and salt, being careful not to over mix. Distributing the batter evenly between the prepared tins, fill cupcake liners approximately Â¾ of the way to the top. Bake for 18 to 22 minutes. Allow them to cool completely before proceeding to the frosting.
1. Combine confectioners sugar to butter.
2. Mix until light, then slowly beat in vanilla and root beer until desired consistency.