Peanut Butter Cupcakes with Chocolate Frosting

Most weekends I know exactly what I want to bake. This past weekend was not one of those weekends. I did not make my mid-week grocery list and had no idea what I was going to make until the  very last minute. All I knew was that I wanted to make something with chocolate and peanut butter. That should come as no surprise- favorite. combination. ever. Anyways, I considered making these Dark Chocolate Peanut Butter Cupcakes, but ultimately decided to switch things up a little bit. Instead of making a chocolate cupcake with peanut butter frosting, I decided to try a peanut butter cupcake with chocolate frosting. Definitely a good decision. 

Despite all of the cupcake recipes on my blog, I recently realized that I have yet to post a recipe for chocolate frosting. This seemed like the perfect opportunity to share my all-time favorite chocolate frosting recipe. It is light and creamy, with just the right amount of chocolate flavor. Just make sure to frost the cupcakes immediately after making the frosting so that the chocolate doesn't have a chance to harden first. So here you have it, another chocolate and peanut butter recipe for the archives. And it is a good one at that!

Peanut Butter Cupcakes with Chocolate Frosting
Cupcake recipe adapted from Martha Stewart's Cupcakes, Frosting recipe from Annie's Eats (originally adapted from Martha Stewart's Cupcakes)

1 3/4 cups all-purpose flour
3/4 tsp baking powder
1/4 tsp baking soda
1/2 tsp salt
12 tbsp (1 1/2 sticks) unsalted butter, at room temperature
1 1/3 cups granulated sugar
2/3 cup creamy peanut butter
3 large eggs
1/2 cup sour cream
1 tsp vanilla extract
1/4 cup buttermilk

Frosting:
9.5 oz. bittersweet chocolate, finely chopped
6 oz. cream cheese, at room temperature
6 tbsp. unsalted butter, at room temperature
2 cups powdered sugar
4 tbsp. Dutch-process cocoa powder
Pinch of salt
2/3 cup + 1 tbsp sour cream

Preheat the oven to 350 degrees F. Line two cupcake pans with paper liners and set aside.

In a large bowl, whisk together the flour, baking powder, baking soda and salt. Set aside. In the bowl of an electric mixer, combine the butter and granulated sugar. Beat until light and creamy, about 3-4 minutes. Add the peanut butter and mix until just combined. Add the eggs, one at a time, mixing until fully incorporated after each addition. Scrape down the sides of the bowl as necessary. Add the sour cream. With the mixer on low speed, add half of the dry ingredients and mix until just combined. Add the buttermilk, followed by the remaining dry ingredients, and mix until combined after each addition.

Divide the batter between the prepared cupcake liners, filling each about 2/3 full. Bake for 18-20 minutes or until an inserted toothpick comes out clean. Let the cupcakes cool in the pan for a few minutes before transferring to a wire rack to cool completely. 

While the cupcakes are cooling, prepare the frosting. Melt the chocolate in a heat-proof bowl set over a pot of barely simmering water. Remove the bowl from the heat and allow to cool until just barely warm. In the bowl of an electric mixer fitted with the paddle attachment, combine the cream cheese and butter. Beat until light and creamy, about 3-4 minutes. Slowly add the powdered sugar, cocoa powder and salt. Beat in the melted chocolate, followed by the sour cream. Mix until smooth and blended. Frost cooled cupcakes immediately so that the chocolate does not harden first.