This quick and easy cake batter is originally from Cook's Illustrated "The Best Recipe Cookbook", which is just the ticket for tried-and-true chocolate cake recipes, only adapted for blissful simplicity. The dense texture makes frosting entirely optional, so I've made this with a sprinkle of powdered sugar instead and optimized the decoration for Valentine's Day. The fact that it is made from cocoa, and quickly, without dirtying a million dishes only adds to its charm. The recipe calls for two 8-inch cake pans, but I used one cake pan and one 12-well mini-muffin pan.
I really think that pouring boiling water over the cocoa is the key to the cake's lush texture and fantastic flavor.
The original recipe also says something about lining the pans with parchment paper, but I used Pam baking spray with the flour in it, and everything slid right out.
Heat the oven to 350°F, and butter and flour your pans.
In a small bowl, whisk together the cocoa, instant coffee, and boiling water and leave the mixture to cool to room temperature, then stir in the vanilla.
In the bowl of an electric mixer on medium-high speed, beat the butter until it's "smooth and shiny," the recipe says, around 30 seconds. Gradually add the sugar and beat until the mixture is "fluffy and almost white", around 3-5 minutes. Add the eggs one at a time, beating a full minute after each addition.
Whisk together the flour, baking soda, and salt. With the mixer on low, add about 1/3 of the dry ingredients, followed immediately by 1/3 of the cocoa mixture and mix until the ingredients are incorporated. Repeat the process twice more. When the batter appears blended, stop the mixer and scrape the bottom and sides with a rubber spatula, then return the mixer to low speed and beat until the batter is lovely and satiny, about 15 seconds longer.
If you're using two cake pans: Divide the batter between them, spread it evenly with the spatula, and pop them in the middle of the oven to cook for 23 to 27 minutes, until they feel just springy when you press them in the center, and a toothpick comes out with a few moist crumbs but nothing that still looks runny.
If you're using a mini-cupcake pan: Scoop half the batter into a Ziploc bag, twist the bag to force the batter into a corner, and snip about a half inch off the corner with a pair of scissors. Squeeze the batter from the bag into the wells, filling each about 3/4 of the way. Fill the cake pan with the remaining batter (including any left in the bag), and pop the pans into the oven to bake (if you're using a silicone pan, stick it on a cookie sheet first).
After you remove your various cakes from the oven, cool them in their pans on a rack for ten minutes, then flip them over and out. To make the stencil for the big cake, I simply cut a heart from the center of a doily and pressed the doily to the surface of the cake before sprinkling it generously and evenly with powdered sugar through a sieve. I also added a tiny sprinkling of pink sugar for romantic effect.