Why is this cake sitting in a bamboo steamer? Because it's been steamed rather than baked for moist, chocolate-y perfection. Check out the stats on this cake: an eight-inch cake containing four ounces of unsweetened chocolate, three tablespoons of butter, and one-half cup of sugar. Five eggs go into the batter. The cake takes eight minutes to cook.
Are you impressed? If not, you either a) don't do much baking or b) don't like cake. Assuming that the latter is logically incoherent, the former possibility invites me to offer some typical measurements for a cake of this size. It's generally common, for instance, for an 8-inch chocolate cake to contain three times as much butter and twice as much sugar, if not more. Thirty minutes, at least, is the standard baking time.
The modest use of butter and sugar, as well as the speed with which the cake cooks, owes entirely to the steamed preparation. Cooked in its bamboo sauna, the cake needs much less fat and liquefied sugar to stay moist. Light but creamy, the texture falls somewhere between a cake and a chilled mousse. Try it for a change from your typical butter-laden holiday baking.
Unlike Western-style kitchens, the line-up of Asian kitchen appliances rarely includes the oven. In lieu of ovens, Asian cooks will often steam their sweets. Japanese and Chinese cakes, such as the sponge cakes served at Cantonese dim sum or Japanese-style cheesecake soufflés, are steamed. Other confections, like Vietnamese and Thai glutinous rice patties, are wrapped and steamed in banana and pandan leaves. Oftentimes, cakes cooked in a steamer taste purer than those baked in the oven; without too much butter, the flavor of the main ingredient really comes through.
Components of the Cake
The majority of this cake is comprised of chocolate and egg. Like a soufflé, this cake is leavened by beaten egg whites rather than baking powder or baking soda, and just one-half cup of cake flour and one tablespoon of rice flour are added to the batter.
In trial runs of the cake, I found that too much flour imparts a dense, gummy heaviness to the cake, while too much chocolate makes it difficult to achieve a perfectly smooth batter that blends well with the beaten egg whites. When melting the chocolate, be sure to finely chop the chocolate before adding it to the double boiler. (A serrated bread knife makes quick work of the task.) Let the chocolate melt undisturbed in the double boiler after it's been taken off the heat. Doing so is a foolproof way of achieving a smooth texture without risking the separation of the oil from the solids in the chocolate.
Finally, I like to add a spike of rum or a spoonful of instant coffee for additional depth. Orange zest and liquor, or vanilla and almond extra, would be fine complements as well.
Steamed Chocolate Cake
- 1/2 cup sugar
- 4 tablespoon water
- 3 tablespoons butter
- 4 ounces unsweetened chocolate
- 1 tablespoon rum
- 5 eggs, separated
- 1/2 cup cake flour
- 1 tablespoon rice flour
With a serrated bread knife, chop the chocolate into fine slivers. Have ready an 8-inch cake pan, fitted with parchment paper on the bottom.
In a double boiler or a glass bowl propped on top of a pot of simmer water, combine the sugar, water, and butter. Let heat for 3 to 4 minutes, until fully melted. Remove the top from the heat and immediately add the chopped chocolate. Set aside for 5 minutes, letting the chocolate melt undisturbed.
Add the tablespoon of rum to the chocolate mixture, stirring to mix all the ingredients together. At this point the chocolate should be fully melted; the mixture should be smooth and glossy.
Add the yolks, one by one, to the bowl, mixing well after each addition. Add the cake flour and the rice flour, mixing until the flour is just incorporated.
In the meantime, beat the egg whites until they form stiff peaks - on high speed in the bowl of a stand mixer, with a hand-held mixer, or by hand.
Mix 1/5 of the beaten egg whites into the batter, stirring well to incorporate. Then gently fold in the rest of the egg whites, taking care not to deflate the mixture. Pour the cake batter into the pan.
Have ready a bamboo steamer or steamer insert with at least 2 inches of water underneath. Bring the water to a gentle simmer. Carefully place the cake pan into the steamer. If you are using a metal pot, wrap the lid in a towel before closing the pot, so that the condensation from the lid doesn't drop onto the cake pan.
Steam for 8 minutes, until the surface and edges of the cake are set but the middle is still soft and custardy when pricked with a knife or skewer. Remove the cake from the steamer and let cool to room temperature, covered with a tea towel. Refrigerate the cake for at least 2 hours, and up to 4 days. The cake should be covered in an airtight container to prevent drying out.