Ingredients
1 1/2 cups confectioners' sugar
3 tablespoons unsweetened Dutch-process cocoa powder
Pinch of salt
5 tablespoons unsalted butter, softened
4 ounces cream cheese, room temperature
7 ounces bittersweet chocolate, melted
2/3 cup sour cream
Preparation
Sift sugar, cocoa powder, and salt into a medium bowl; set aside.
Put butter and cream cheese into the bowl of an electric mixer fitted with the paddle attachment. Mix on medium-high until fluffy. Reduce speed to low. Gradually add sugar mixture. Mix in chocolate and sour cream. Use immediately.