Red Velvet Sheet Cake
By now many people know the purported origin story of red velvet cake—a nerdy tale involving a chemical reaction between natural cocoa powder and baking soda. While that may have been the case in ancient times, the red velvet of this century is defined by its startling color, a fire engine red so bright it stains your tongue for hours. Somewhere along the way the flavor began to matter less than the hue. Red velvet was no longer just a cake—it was a lifestyle. It was a cheesecake, an air freshener, a candle to be lit while you luxuriate in the bath. And this is a shame because red velvet wants to be more, to do better, to go beyond just being a vehicle for cream cheese frosting and red dye 40.
Here then is our apogee of red velvet cake. It’s red, yes, but subtly so, like the flocked lining of a luxury bag. Most importantly, it tastes perceptibly of chocolate. Nothing like the bitter intensity of fancy dark chocolate, more like the warming milkiness of hot cocoa in a cup. Unsweetened chocolate proves to be a winner: The cocoa butter in the chocolate makes the cake extra fudgy and rich, with just the right amount of squishiness. We like Guittard, Ghirardelli, or Lindt.
Bleached all-purpose flour is an absolute imperative. In a cake as soft and tender as this one, with a higher amount of sugar than flour (called a high-ratio cake in professional circles), only bleached flour can absorb and withstand the extra moisture. With unbleached flour, the cake will be dense, bearing a visible band of gumminess toward the bottom.
The amount of cream cheese frosting, lightened by a generous pour of heavy cream, is modest, designed to show off the cake. Double up if you prefer a thicker blanket of icing.