3/4cup, 1 1/2 sticksunsalted butter, at room temperature
18ouncesbittersweet chocolate, finely chopped
1 1/2cupssour cream
Instructions
To make the cupcakes, preheat the oven to 350˚ F. Line standard cupcake pans with liners. In a small bowl, whisk together the cocoa powder and hot water until smooth. In another bowl, whisk together the flour, baking soda, baking powder, and salt.
In a medium saucepan over medium-low heat, combine the butter and the sugar. Stir to combine, until the butter is melted and remove from heat. Transfer to the bowl of a stand mixer fitted with the 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 10 minutes, then transfer to a wire rack to cool completely.
To make the ganache, place the chopped chocolate in a medium heat proof bowl. In a small saucepan bring cream and corn syrup to a simmer over medium-high heat. Remove from heat and pour over chocolate. Let stand 2 minutes. Starting in the center and working outward, stir melted chocolate into cream until mixture is combined and smooth. Transfer the bowl to the refrigerator to chill and thicken. Whisk every 5 minutes to help it cool evenly. Once the mixture is slightly thickened you are ready to fill the cupcakes.
To assemble the cupcakes, place ganache filling into a decorating bag fitted with the number 230 round decorating tip. Insert the tip into the center of the cupcake and gently squeeze the ganache into the center of the cupcake. Repeat with remaining cupcakes.
To make the frosting, melt the chocolate in a heat-proof bowl set over a pot of simmering water. Stir until smooth and set aside to cool 20-30 minutes. Sift together confectioner’s sugar, cocoa, and salt. 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 add sugar mixture and mix until incorporated. Beat in the melted and cooled chocolate and then the sour cream. Continue beating until the mixture is smooth and well blended. Place frosting into decorating bag fitted with the 1M decorating tip and approximately 1/4″ above cupcake top at a 90° angle to cupcake surface, pipe a spiral of icing, beginning at the outer edge and working inward.