Most western-style cakes are intended for baking in an oven, but in cultures where ovens aren't traditional, cakes are often steamed. The cooking temperature is lower when steaming. but the moist air transfers heat more effectively, so baking times remain the same at 20 to 40 minutes depending on the size of the pan. Round bamboo steamers will usually accommodate an 8-inch or 9-inch cake pan.
Choose a steamer that's deep enough for your cake to rise completely without coming into contact with the lid. It should also be at least 2 inches wider than your pan, so there's 1 inch of space on all sides for steam to circulate.
Fill the bottom of a wok with 2 to 3 inches of water, enough to bake the cake without boiling dry. If you don't have a wok, select a saucepan the same diameter as your steamer. Bring the water to a boil while you prepare your cake.
Spray your cake pan evenly with your favorite cooking spray. If the recipe specifies greasing and flouring your pan, use a piece of wax paper to apply a thin layer of shortening to its interior surfaces. Then add 2 tablespoons of flour to the pan, and tilt and tap the pan until flour clings to all of its surfaces. Shake out any excess flour.
Prepare your cake as directed in the recipe. Pour the batter into your prepared cake pan. Lift the lid from your steamer, and wait for the cloud of hot steam to dissipate. Slide the cake pan into the steamer, and replace the lid.
Steam the cake for the same length of time it was supposed to bake in the oven. When the time is up, remove the steamer's lid, and wait for the steam to dissipate. Insert a cake tester in the middle of the cake. If it comes out clean, the cake is finished.
Remove the cake from your steamer, and allow it to rest for at least 10 minutes before turning it out onto a cooling rack. Steamed cakes have a more delicate texture than baked ones and can easily be flattened or become misshapen if they're turned out too soon.