Instructions

Make the cupcakes:

1. For the cupcakes: Preheat the oven to 350F degrees. Line a 12-cup cupcake/muffin pan with cupcake liners. Set aside.
2. Melt the butter and chocolate together in the microwave. Microwave in 30 second increments, stirring between each time. You may also melt the butter and chocolate over low heat on the stovetop. Stir until smooth and set aside to slightly cool.
3. In a medium sized bowl, toss the cocoa powder, flour, baking soda, baking powder, and salt together until thoroughly combined. Set aside. In a large bowl, whisk the eggs, sugar, brown sugar, and vanilla together until smooth. Add the cooled butter/chocolate and whisk until smooth. Add half of the flour mixture, then half of the buttermilk. Repeat until everything is added. Stir until *just* combined; do not over mix. The batter will be very thick like pudding.
4. Divide the batter between 12 liners in your cupcake pan. Put a heaping (really heaping) teaspoon of peanut butter on each cupcake and swirl. Bake for 18 minutes, or until a toothpick inserted in the center comes out clean. Allow to cool completely before frosting.

Make the frosting:

1. In the bowl of an electric mixer fitted with the paddle attachment, whip butter for 5 minutes on medium speed (I use “4” on my KitchenAid). Butter will become pale & creamy.
2. Add the powdered sugar, milk, and vanilla extract. Mix on low speed for 1 minute, and then on medium speed for 5 minutes. Add in crushed Oreos and mix to incorporate completely, about 1 minute.
3. Frost cooled cupcakes immediately. If desired, top with half an Oreo or a mini Oreo to garnish.