Double Chocolate Cupcakes with Chocolate Cream Cheese Frosting

More cupcakes!  Since I'm a little behind on posting, I have a few treats to share from before my hiatus.  My roommate (no longer... tear) celebrated her birthday a few weeks ago.  I whipped up these double chocolate cupcakes for the big day.  Rich but delicious!

Double Chocolate Cupcakes
Source: adapted from Annie's Eats
Yield: about 32 cupcakes

Ingredients:
For the cupcakes:
¾ cup unsweetened Dutch-process cocoa powder
¾ cup hot water
3 cups all-purpose flour
1 tsp. baking soda
1 tsp. baking powder
1¼ tsp. coarse salt
1½ cups (3 sticks) unsalted butter
2¼ cups sugar
4 large eggs, at room temperature
4 tsp. vanilla extract
1 cup sour cream, at room temperature

For the frosting:
14 oz. bittersweet chocolate, finely chopped
9 oz. cream cheese, at room temperature
9 tbsp. unsalted butter, at room temperature
3 cups confectioners’ sugar, sifted
6 tbsp. unsweetened Dutch-process cocoa powder
Pinch of salt
1 cup plus 2 tbsp. sour cream

Directions:
To make the cupcakes, preheat the oven to 350˚ F.  Line standard cupcake pans with paper liners.  In a small bowl, whisk together the cocoa powder and hot water until smooth.  In a medium bowl, whisk together the flour, baking soda, baking powder, and salt; set aside.

In a medium saucepan, combine the butter and the sugar over medium heat.  Heat, stirring occasionally to combine, until the butter is melted.  Remove the mixture from the heat and transfer to the bowl of an electric mixer fitted with a paddle attachment.  Beat on medium-low speed, 4-5 minutes, until the mixture is cooled.  Mix in the eggs, one at a time, scraping down the sides of the bowl as needed and beating well after each addition.  Mix in the vanilla and then the cocoa mixture and beat until incorporated.  With the mixer on low speed add in the dry ingredients in two batches, alternating with the sour cream, beating just until combined.

Divide the batter between the prepared cupcake liners, filling them about ¾ of the way full.  Bake 18-20 minutes or until a toothpick inserted in the center comes out clean, rotating the pans halfway through baking.  Allow the cupcakes to cool in the pan 5-10 minutes, then transfer to a wire rack to cool completely.

To make the frosting, melt the chocolate in a heat-proof bowl set over a pot of simmering water.  Set aside to cool until just barely warm.  In the bowl of a stand mixer fitted with the paddle attachment, beat the cream cheese and butter on medium-high speed until pale and fluffy, about 3-4 minutes.  Gradually mix in the confectioners’ sugar, cocoa powder and salt.  Beat in the melted and cooled chocolate and then the sour cream.  Continue beating until the mixture is smooth and well blended.  Frost cupcakes immediately.