I've long touted the wok as the most versatile pan in the kitchen. Now I aim to prove that claim. You already know how to shop for a wok, now it's time to learn how to use it.
Steaming involves placing food on a perforated surface above a small amount of simmering water and covering it with a lid. As the water evaporates, the steam it creates rises, transferring heat energy to the food and cooking it. Although steam can get hotter temperature-wise than boiling water can, it actually cooks far more gently because it is less dense.
It is the way to cook delicate pastry-based foods like dumplings, shu-mai, and bao, the sweet leavened steamed buns that are a popular form of dim sum. Unlike a vigorously boiling pot of water which can batter and bruise delicate pastries, steamed food remains in one place as the hot steam lazily circulates around it.
Green vegetables are another perfect candidate for steaming. Unlike blanching, which requires bringing a huge pot to a boil, vegetables can be rapidly steamed over just a couple cups of simmer water. If I were the type of person who believed that good nutrition requires an impassioned appraisal of every morsel that crosses my lips, I'd point out that by steaming foods, you retain some of the nutrients that would be diluted and washed away by boiling.*
*I'm thankfully not that kind of person, so I won't mention it.
Steaming is also a good way to cook delicate shellfish and seafood, or to par-cook soft, fatty cuts of meat before stir-frying, as you'd do with pork belly before slicing it and frying it with hot peppers in the classic Sichuan dish of double-cooked pork. I like to steam eggplant before stir-frying it in order to soften it and help it soak up more flavor from sauces.
Traditional Chinese steamers are made from bamboo, and they still remain the standard for home use today. They are cheap, efficient, and almost perfectly designed to do the job. The great thing about bamboo steamers combined with woks is that >because of the sloping shape of a wok's sides, any sized steamer will work in your wok, so long as it's diameter is smaller than your wok's.
Steamers also stack, allowing you to steam at least three or four different foods over the same wok of simmering water. A 10-inch steamer (I prefer the 10-inch by Joyce Chen) will be sufficient for most home cook's needs. I keep a few 12-inch steamers on hand for when I have dim sum parties that require large quantities of steaming. A smaller 6 or 8-inch steamer can also make for fabulous presentation at the table.
How to Steam Food
Steaming always involves starting with a small amount of water simmering in your wok. I add water until it is about halfway up to the bottom of where the steamer sits. So for a small 6-inch steamer, you'll only need a cup or so of water, whereas for a 12-inch, you'll need closer to three cups. Bring the water to a boil over high heat, then reduce the heat so it maintains a gentle simmer.
Vegetables are the easiest. Just place them in a thin, even layer in the steamer, cover, set them in the wok, and steam until they're done.
Proteins can also be cooked directly in the steamer. Just make sure the arrange the food in a single layer, and leave enough space between pieces for the steam to circulate.
Dumplings and pastries are a little more difficult, since they have a tendency to stick to the bamboo as they cook. There are two easy ways to solve this problem. If you have any lettuce or cabbage on hand, you can steam a few leaves for a couple of minutes until they are wilted, then use them to line the bottom of the steamer basket. Place your dumplings directly on top of the wilted lettuce leaves, and they will prevent them from sticking.
Alternatively, if you don't have any leaves on hand, you can create a parchment-paper liner to fit any sized wok. It's the same process as the one used to make a parchment paper lid.
What if I Don't Have a Bamboo Steamer?
If you find yourself at a friend's house who has a wok but no steamer, it's easy to hack one together with a disposable aluminum pie plate and any large pot lid. All you have to do is poke a whole bunch of holes in the aluminum pie plate with a skewer, invert it and place it in your wok of simmering water, place the food directly on top of it, and cover the whole thing with a lid (any large pot lid will fit on a wok).
Really, steaming couldn't be any easier in a wok. The only thing to keep an eye out for is your water level. If you accidentally let the water cook off, the wok metal will start overheating, and can eventually char the bottom of your bamboo steamer, or even cause a fire if you're really unlucky. But of course, no Serious Eater would ever let it go that far, right?