Chocolate Peanut Butter Cupcakes

I delivered four dozen cupcakes to RAYS (Renton Area Youth and Family Services) this afternoon.  Washington is afire with autumnal colors right now, and in celebration of falling leaves (and also some favorite Halloween candy flavors), it seemed appropriate to make chocolate cupcakes with peanut butter frosting, adorned with themed fondant toppers shimmered with edible luster dust.

I used a Wilton 2D piping tip to pipe the cupcake frosting, with the intention of creating the ruffled, serrated look of a dessicated Fall leaf.

Scroll down for my cupcake recipe!

I marbled together three different colors of fondant for this effect -- olive green, orange, and candy-apple red. I used silicone embossing mats to create the designs, dusted the filigree toppers delicately with bronze edible luster, and painted the leaf toppers with Old Gold and Pale Gold luster dusts mixed with vodka (which evaporates, leaving a lustrous shimmer behind).

Moist Chocolate Cupcakes with Peanut Buttercream 
(Makes 24)

For the cupcakes:
1 oz bittersweet chocolate (chopped)
1/2 cup cocoa powder (Dutch processed)
1 cup boiling water
2 cups cake flour
1/2 tsp salt
1 teaspoon baking soda
1-1/2 cups light brown sugar (packed)
2 sticks (1 cup) unsalted butter (at room temp, cubed)
1/4 cup sour cream
4 eggs

  • Preheat oven to 350. Line two 12-cup muffin tins with paper or foil cases. 
  • Combine the chocolate and cocoa powder in a heatproof bowl; pour over the boiling water and mix until smooth. Allow to cool to room temperature (4 hours outside the fridge; 1 hour inside the fridge - but whisk it every 15 mins if you cool it in the fridge).
  • Thoroughly whisk together the flour, salt, baking soda, and brown sugar in the bowl of your KitchenAid (or use a handheld mixer).
  • On low speed, add the cubes of butter and beat until the mixture resembles dough (this takes about 30 seconds).
  • Separately, whisk together the sour cream and eggs until combined. Pour the egg mixture into the 'dough' mixture on low speed until combined, then turn the mixer up to medium-high speed and beat until fluffy and light (about 2-1/2 minutes), scraping down the sides of the mixer bowl with a spatula every so often.
  • Turn the mixer down to low, and slowly add the cooled chocolate mixture; mix for 20 seconds or so.
  • Divide the batter evenly among all the muffin cases (I use a 1/3-cup stainless-steel measuring cup for this task; an ice-cream scoop works very well, too).
  • Bake for 25 mins or until the top springs back when you press the cupcake in the middle with your fingertip.
  • Allow to cool in the muffin pans for 10 minutes, then remove the cupcakes to a wire rack to cool completely (don't frost them before they're cool, even if, like me, you have the patience of a ravenous two-year-old).

For the buttercream frosting:
2 sticks softened butter (unsalted)
1-1/2 cups creamy peanut butter (I recommend all-natural, unsweetened PB for this)
1/2 teaspoon salt
2 teaspoons good vanilla extract (as always, I use Nielson-Massey bourbon vanilla)
2/3 cup milk (you may need a tablespoon or two extra, depending on your climate, etc)
8 cups powdered sugar, sifted into a bowl (yeah, I know it's a lot - see my note, below)

(Note: This frosting is a LOT sweeter than the meringue buttercreams I usually use to frost cupcakes with, but I feel that to replicate the Reese's peanut butter cup flavor successfully, you need the cloying sweetness of a traditional powdered-sugar frosting like this.)

  • Cream the butter, peanut butter, salt, and vanilla.  
  • Slowly add the powdered sugar, one cup at a time, alternating with the milk, until the frosting is smooth and the smell of sweet, salty peanuts fills your kitchen.