From America's Test Kitchen Season 7: Dark Chocolate Desserts
Cupcakes shouldn’t be complicated, but homemade versions can take a lot of time and store-bought mixes don’t deliver good chocolate flavor. We wanted the consummate chocolate cupcake—one with a rich, buttery flavor, a light, moist, cakey texture, and just the right amount of sugar—but we wanted it to be almost as quick and easy to make as the cupcakes that come from a box.
For the mixing method, we found that the melted-butter method often used for mixing muffins, quick breads, and brownies—a method that requires no mixer and no time spent waiting for butter to soften—worked best. The same procedure won out over the more conventional creaming method for our cupcakes, delivering a light texture with a tender, fine crumb. Moving on to tackle our desire for deep chocolate flavor, we found that a combination of cocoa powder and bittersweet chocolate delivered deep chocolate flavor and that mixing the cocoa powder with the butter and chocolate as they melted (rather than adding the cocoa to the dry ingredients) made the chocolate flavor even stronger and richer. Sour cream gave our cupcakes moistness and a little tang, while just the right amounts of baking soda and baking powder helped them rise to a gently domed shape that was perfect for frosting.
Makes 12 cupcakes
This recipe does not double very well. Cupcakes made from a doubled batch and baked side by side in the oven yield a slightly compromised rise. It's best to make two separate batches and bake each separately. Store leftover cupcakes (frosted or unfrosted) in the refrigerator, but let them come to room temperature before serving.