The Best Chocolate Cupcakes

Preheat oven to 350 degrees and line a standard cupcake pan with 12 cupcake liners.
Add the granulated sugar and softened butter to a large bowl. Cream together with an electric mixer on high speed for 1-2 minutes until fluffy.
(You can also use a stand mixer fit with a paddle attachment.)
1/4 cup (56 g) unsalted butter, softened, 3/4 cup (150 g) granulated white sugar
Then add in the egg, egg yolk and vanilla and mix on medium speed until light and fluffy, about 1-2 minutes.
1 egg, at room temperature, 1 egg yolk, at room temperature, 1 tsp vanilla
Next mix in the milk and sour cream on low speed.
1/4 cup (61 g) sour cream, at room temperature, 1/2 cup (120 ml) whole milk, at room temperature
In a small bowl whisk together the flour, cocoa powder, baking powder, baking soda, salt and espresso powder.
1 cup (125 g) all-purpose flour, spooned and leveled, 1/4 cup + 1 tbsp (25 g) Dutch process cocoa powder, 1/2 tsp baking powder, 1/2 tsp baking soda, 1/4 tsp salt, 1 tsp espresso powder
Add the dry ingredients to the wet ingredients and combine on low speed.
Fill each cupcake liner ¾ of the way full with batter. Bake the cupcakes for 17-20 minutes, or until a toothpick/cake tester comes out clean from the centers.
Let the cupcakes cool in the pan for 10 minutes then transfer to a cooling rack to cool completely.

While the cupcakes are cooling make the frosting by adding the softened, unsalted butter and salt to a medium sized bowl. Mix with an electric mixer until the butter is pale in color and fluffy, about 5-10 minutes.
1 cup (224 g) unsalted butter, softened, 1/4 tsp salt
Add in the melted and slightly cooled dark chocolate and combine on medium speed.
6 oz. (170 g) dark or semi-sweet chocolate, melted and slightly cooled
Next sift in the Dutch process cocoa powder and powdered sugar, a little at a time. Mix on low speed until combined, then mix on high until fluffy.
1/4 cup + 2 tbsp (30 g) Dutch process cocoa powder, 2 cups (260 g) powdered sugar
Add in the heavy cream, a tablespoon at a time. Mix on high speed until the frosting is light and fluffy, about 1-2 minutes.
(Add the heavy cream as necessary. If the frosting is light and fluffy after only two tablespoons, don't add the full amount. If it's still too dry after 3 tablespoons, add more.)
2-3 tbsp (30-45 ml) heavy cream

Once the cupcakes are cool, add the dark chocolate buttercream to a large piping bag fitted with a decorative tip.
Pipe a generous amount of frosting onto the tops of each cupcake. Serve right away.

Course: Dessert

Cuisine: American

Keyword: chocolate cupcakes, cupcakes