Chocolate-Chile Frosting - Rick Bayless

Ingredients

• 12 ounces Mexican chocolate roughly chopped
• 6 ounces bittersweet chocolate, roughly chopped
• 3/4 cup powdered sugar
• 3/4 cup sour cream
• 1 1/2 teaspoons vanilla extract, preferably Mexican
• 3/4 teaspoon ancho chile powder
• 1/3 teaspoon chipotle chile powder
• 8 ounces (2 sticks, 16 tablespoons) unsalted butter, room temperature, cut into 8 pieces