Devil's Food Cupcakes:
1 cup all-purpose flour
1/4 cup unsweetened cocoa powder
3/4 tsp baking soda
1/4 tsp salt
1/2 firmly packed light brown sugar
4 tbsp unsalted butter, room temp
1 large egg, room temp
1 tsp vanilla
1/2 cup lukewarm water
1/4 cup buttermilk
Line 12 muffin tins with cupcake liners and preheat oven to 350 degrees.
Sift together all dry ingredients in a medium bowl. In another bowl, beat the butter and both sugars on med-high speed until light and fluffy. About 3 minutes. Add the egg and vanilla and beat until combined. Add the flour mixture in 3 additions alternating with the water and buttermilk, beginning and ending with flour. Beat until just combined, do not over mix.
Divide the batter evenly into the prepared muffin tins and bake for 18-20 min.
Peanut Butter Frosting:
6 tbsp unsalted butter, room temp
3/4 cup peanut butter
1/4 cup heavy cream
2 cup powdered sugar
Beat the butter and peanut butter on medium speed until smooth. Add the heavy cream and continue beating. Gradually add the powdered sugar and beat until smooth and well combined.