3 cake chocolate frosting alexandra Recipes

unsalted butter , plus additional for cake pans, baking soda, kosher salt, baking powder, all-purpose flour, eggs, granulated sugar, vanilla extract, sour cream, coarsely chopped semisweet chocolate, cool water, plus more for the double boiler, cream of tartar, granulated sugar, egg whites, room temperature, light corn syrup, vanilla extract

eggs, granulated sugar, mayonnaise , such as hellmann s, all-purpose flour, baking powder, baking soda, cocoa powder, instant coffee , optional, salt, water, egg whites, granulated sugar, cream of tartar, light corn syrup, vanilla, dark chocolate , for grating, special equipment : 2 round cake pans, 9 inches in diameter; 1 metal (preferably offset) spatula for frosting the cake; 1 instant-read thermometer