Devil's Food Cupcakes

(from Martha Stewart's "Cupcakes")

I think - no, I know - this was the first time I had cupcakes (by choice) on my birthday. What is this brave new world? The only catch with these was that the icing just didn't come out as planned at all. I mean, it was gooey and delicious, but something must've gone wrong somewhere, because it didn't look like cupcake icing. I'd recommend the icing I used for the Devil's Food Chocolate Layer Cake.

(Makes 12 cupcakes - for easier measurements, and more cupcakes, double the amounts below)
3/8 cup unsweetened cocoa powder
3/8 cup hot water
1 1/2 cups flour
1/2 tsp baking soda
1/2 tsp baking powder
5/8 tsp coarse salt
1 1/2 sticks unsalted butter
1 1/8 cups sugar
2 large eggs, room temp
1/2 tbsp plus 1/2 tsp pure vanilla extract
1/2 cup sour cream, room temp
(Plus frosting)

1. Preheat oven to 350. Line muffin tins with paper liners. Whisk together cocoa and hot water until smooth. In another bowl, whisk together flour, baking soda, baking powder, and salt.

2. Melt the butter with the sugar in a saucepan over medium-low heat, stirring to combine. Remove from heat and pour into a mixing bowl. Turn your electric mixer to medium-low speed and beat until mixture is cooled. Add eggs one at a time, beating until each is incorporated. Add vanilla, then cocoa mixture, and beat until combined. Reduce speed to low and add the flour mixture in two batches, alternating with the sour cream, beating until just combined after each addition.

3. Divide the batter evenly among lined cups, filling each 3/4 full. Bake, rotating tins halfway through cooking. At about 20 minutes, use a piece of spaghetti to test if the cupcakes are done by inserting it into a cupcake and seeing if it comes out clean.

4. Remove cupcakes from oven and allow to cool before spreading cupcakes with frosting.