1 3/4 cup featherlight flour
1 scant teaspoon xanthan gum
2 cups sugar
3/4 cup cocoa
2 teaspoons baking powder
1 teaspoon salt
1 cup buttermilk (1 tablespoon vinegar, almost 1 cup heavy whipping cream)
1/2 cup canola oil
2 eggs
1 teaspoon vanilla
1 cup hot water
24 Mini Reece's Peanut Butter cups (You'll need more for the top of the cupcake!)
Start by making the homemade buttermilk. Put 1 tablespoon vinegar in a 1 cup measuring cup, then fill the rest of the cup with heavy whipping cream. Let it sit for at least 5 minutes.
Combine dry ingredients in your mixer. In a small bowl add buttermilk, oil, eggs, vanilla, and mix with a fork. Turn the mixer on low speed and gradually add wet ingredients to dry ingredients. Stop and scrape down the bowl. Return to low speed and gradually beat in hot water. Mixture will be very thin.
Fill cupcake liners 2/3 full. Bake at 350ยบ for 10 minutes. While baking, remove foil from 24 peanut butter cups. After the 10 minutes, open the oven and pull the rack out so you can place peanut butter cups in the center of the batter. Push down until flush with batter. Slide back in the oven and bake for another 8 - 10 minutes. As it bakes, the batter will puff up around the peanut butter cups. Test the side of the cupcake (where there is no peanut butter cup) to see if cupcake is done.
Cool on wire racks. When completely cool, frost the cupcakes with the peanut butter frosting, using a large star piping tip.
Peanut Butter Frosting
1 1/3 cups creamy peanut butter
2 cubes butter, softened
2 cups powdered sugar
12 Mini Reece's Peanut Butter cups
Cream peanut butter and butter together. Gradually add powdered sugar. Whip on high speed until light and fluffy. Transfer icing into a piping bag with a large star piping tip. Pipe around the cooled cupcake, working towards the center. Top with half a mini Reece's Peanut butter cup.
