Note: I've used this recipe for mini cupcakes, round layer cakes, large rectangular cakes, you name it. For mini cupcakes, I'd cut the baking time down to about 15 minutes per cupcake and start checking the center with a toothpick from there. For cakes, a full recipe makes two 9-inch round cakes, and make sure to adjust cooking time to 30-35 minutes and check with cake tester until done.
One Bowl Chocolate Cupcakes
(from the Martha Stewart Baking Handbook)
-makes 30 standard size cupcakes (I halved this for the party and got 15)
2 1/2 cups all-purpose flour
1 1/4 cups cocoa powder
2 1/2 cups granulated sugar
2 1/2 teaspoons baking soda
1 1/4 teaspoons baking powder
1 1/4 teaspoons salt
2 large whole eggs + 1 large egg yolk
1 1/4 cups milk
1/2 cup + 2 Tablespoons vegetable oil
1 1/4 teaspoons pure vanilla extract
1 1/4 cups warm water
Icing of your choice, perhaps this recipe for buttercream
Preheat oven to 350F. Line two standard 12-cup muffins pans with paper liners (see pretty gold ones for the Oscars, of course). Into the large bowl of an electric mixer, whisk together flour, cocoa, sugar, baking soda, baking powder, and salt. Attach bowl to the mixer fitted with the paddle attachment (or regular beaters on your hand mixer) and add eggs and yolk, milk, oil, vanilla, and warm water. Beat on low speed until smooth and combined, roughly 3 minutes. Scrape down the sides of the bowl as needed.
Fill each paper liner roughly 2/3 full of batter. Bake, rotating pans halfway through, until a cake tester or toothpick inserted in the center of a cupcake comes out clean, 20 to 25 minutes. Cool pans on rack for roughly ten minutes. Remove cupcakes in liners from pan carefully and place onto rack to cool completely, top sides up.
Frost cupcakes to your fancy. I'll admit I cheated and bought coconut-pecan frosting from the store, to make these more German. I used my trusty ice cream scooper to portion out icing with the intention of spreading it over the whole top of the cupcake, but it looked so artsy that I left it that way. Cupcakes can be refrigerated in an airtight container for up to 5 days (but good luck getting them to last that long).