This is a quick buttercream frosting with a rich chocolate taste. Unlike other recipes, this one doesn't form a "crust" if left to sit. Makes enough to frost one 9-inch 2-layer cake. Can be made with milk, semisweet, or bittersweet chocolate.Based on a recipe by Yvonne Ruperti, Cook's Illustrated, March & April 2008.
8ounceschocolatemilk, semisweet, or bittersweet is fine
20tablespoonsunsalted buttersoftened to 60 to 65 degrees
1cupconfectioner's sugar
3/4cupDutch-process cocoa powder
pinchtable salt
3/4cuplight corn syrup
1teaspoonvanilla extract
Instructions
Heat water in bottom of double boiling until hot but not boiling. In top part of double boiler add chocolate and corn syrup. Stir until chocolate is just melted, remove from heat and allow chocolate to cool to 85 -100°F.
In food processor, process butter, sugar, cocoa, and salt until smooth, about 30 seconds, scraping sides of bowl as needed. Add vanilla. Scrape sides of bowl, add chocolate - corn syrup mixture, then pulse until smooth and creamy, 10 -15 seconds. Frosting can be used immediately or within 3 hours. For longer storage, refrigerate frosting, covered, and let stand at room temperature for 1 hour before using.
Notes
Pairs well with Yellow Cake https://catherinechristiano.com/2020/07/19/yellow-cake/.