Most cooking involves finding the sweet spot, and that’s particularly true with baking, where perfect cakes require the perfect oven temperature.
But oven heat can vary a surprising amount, leading to inconsistent results. If the cake’s a touch too hot, it dries out and bubbles up in the middle. Too cool and it doesn’t rise enough, leaving you with a dense flop.
Which had us wondering... What if, to make an ultra-moist, evenly cooked cake, we got rid of the oven altogether?
In areas of the world with fewer home ovens, cakes often spring to life on stovetops, relying on the consistent temperature of steam. It’s a better way to “bake” an unimaginably moist, tender cake every time.
Stovetop steaming is typical in some Western recipes—Boston brown bread and British Christmas pudding, for instance—but today it’s mostly practiced in Asian countries for desserts, like almond-scented nian gao, served at Chinese New Year; Korea's red-bean pat siruteok; and kue putu, made inside a bamboo tube in Indonesia.
The technique owes its success to how steam relates to the starch and gluten in the batter. In a dry oven, the interior of the cake never gets above about 200°F because much of the moisture is lost to evaporation as it reaches the boiling point. But in the steamy environment of a simmering pot, the temperature throughout stays an even 212°F.
Since steam has five times the energy of air at the same temperature, it agitates the batter, sort of punching the cake from the inside, causing it to set more quickly. The water that would otherwise evaporate is retained in a stronger cake crumb, resulting in a uniformly moist cake.
At Milk Street, we wanted to adapt this simple, effective technique to a classic chocolate cake. A Dutch oven provided the right size for a steaming pot, and placing a coil of scrunched-up foil on the bottom was an easy way to keep the cake pan above the water line.
We left the stand mixer in the cupboard, opting for a simple two-bowl mixing method, and poured the batter right into the prepared pan. In little more than 20 minutes, we had a light, ultra-moist chocolate cake.
One element we lost by steaming was the browned edges that result from the Maillard reaction, when heat reacts with the sugars and proteins in the batter. Steaming, however, cleared the way for a cleaner, more chocolate-forward flavor. A touch of espresso powder added complexity and hinted at those roasted aromas that would have developed during baking.
Our stovetop recipe strikes a balance of being rich but not dense. Its velvety simplicity pairs well with a scoop of vanilla ice cream or just a dusting of powdered sugar.