Why a wok?
Of the four most basic methods of cooking -- immersion in liquid (boiling, stewing), immersion in oil (frying, sautéing), cooking in vapour (steaming) and dry heat (baking, broiling, roasting) -- the wok is used for all but the last. The reason for this, as well as the cooking methods, can be found in the geography and history of the wok's origins.
In China, fuel was, and remains, relatively scarce. As in all regional styles of cooking, food is prepared based on the available ingredients and limited to the available methods of cooking. Fuel is an important consideration.
Europe's trees and peat provided ample fuel to heat food for long periods, something required both in baking and in deep frying. Because the technology needed to make metal cookware was also common there, it is from Europe these cooking methods come. In less developed lands, food was cooked directly in or next to a fire or was cooked on rocks heated in a fire. Some cultures created an earth oven using a dug-out pit and rocks. This, however, still required considerable fuel.
The trick in fuel efficiency, as in aerodynamic, is the shape. The wok's form allows a large surface area to heat quickly and efficiently. As the heat spreads out from the bottom and rises, the sloped sides of the wok catch it, unlike the vertical sides of western pots.
Together with a rounded shovel-like implement, ingredients can be moved around quickly to ensure all are cooked. The gently sloping shape also allows food to be pushed aside and remain hot while the accompanying sauce is made in the middle, where the heat from a dying fire is still strong. Bear in mind that the fire was rarely made with more than a handful of sticks and some dry grass. A PBS documentary on China happened to show peasants cooking an entire sea bass in a wok with a fire built from five or six small sticks.
The form also allows one to lay a couple of sticks across the inside of the wok to support food to be steamed, usually vegetables or fish. Steaming is more efficient than boiling, and heating water to boiling takes a relatively large amount of fuel. Steaming requires only a small amount of water to be heated.
Another factor in Chinese cooking methods was that the idea of bringing a knife to the table, unlike in Europe, was considered unthinkable. This came, in part, from the practical idea that one is never certain of guests' motives. Additionally, some Buddhist concepts of harmony played a part in determining dishes' aesthetics, flavours and form. Therefore, all cutting was done in the kitchen and all food prepared in bite-sized pieces. This remains the hallmark of Oriental food and is the reason it can be eaten with a simple pair of chopsticks and, occasionally, a spoon.
In the West, there are a few basic wok forms which can be found. The traditional, round-bottomed, hammered steel or iron wok is the best. There are two variants: the shallow 36cm (14") in diameter and 9cm (3.5") high used for general cooking, and a deeper version with the same diameter but about 12cm (4.5") deep, used mainly for steaming, frying and soups. While the traditional form has two steel "loop" handles, the former may have a long wooden handle with or without an opposing steel handle.
Similar to this is the flat-bottomed wok, which accommodates flat stovetops better. However, most woks come with fire rings to cradle a curved wok above the burner so the flat base shouldn't be necessary. A flattened bottom causes heat to concentrate on the bottom and creates an area the shovel and scoops can't reach.
Modern production allows easy casting and stamping, but neither the cast aluminium nor stamped stainless steel have the heat retention and distribution properties of the hammered mild steel used for traditional woks.
Also to be found in department stores are stovetop and electric woks with Teflon and other non-stick coatings. Seasoning a steel wok correctly, however, will give a finish which is not only non-stick but is also not susceptible to scratching.
It's not just the Chinese who use woks, though; they're used throughout southeast Asia. The wok made its way to India, too. The traditional Indian iron wok is called a Kadhai, on average about 13" (33cm) wide and 3 inches (8cm) deep and considerably thicker and heavier than the Chinese wok. This article doesn't cover seasoning cast iron, which is ´seasoned differently according to the iron's finish.
What do I do?
First, check to see if you have a gas stove. If not, get one. Gas stoves provide the most heat and are the most controllable heat sources. Next best is an electric stove, either the coil or plate type. With this you will need to use the fire ring. Woks don't work so well on ceramic or induction stovetops. The flat-bottomed version of the traditional wok will function better on these.
Using the fire ring limits the amount of heat received by the upper areas of the wok and are some hindrance. Seasoning a wok requires a lot of heat for a minimum of 20-30 minutes. It's difficult to hold the sides of a flat-bottomed wok over the heat for any length of time. Finally, most gas camping stoves can't provide enough heat. The flame itself is usually smaller than a normal cooktop and propane burns cooler than natural gas. You need around 4,500BTU of heat for this to work well.
You also need very good ventilation; smaller stovetop vents don't pull a sufficient amount of air to clear all the smoke generated, and this process creates creates a lot of heat and smoke.
The first thing you should do with a new wok is use heavy-duty cleaner to remove the machine oil used both in production and as protection against rust. You can use a scouring pad, but fine steel wool pads aren't going to hurt it. After it's clean, use standard dish soap with a sponge or brush to clean up anything left, like saponified oil and steel wool remains. Do this twice.
When you're done, the wok should be shiny and have that smell of raw steel. Do not let water drops sit on this! Wipe it down with dry paper towels immediately, inside and out.
When you're ready to begin (do it within a few hours or the wok will start to rust), put the wok on the stove at the highest possible heat. For smaller stoves, use the dome cover to help keep the heat in. The metal should start to darken within five minutes on a gas stove and eight on electric. It could take twice as long, depending on the heat output of your stove.
Once the steel starts turning, slowly move the wok radially so that the rim approaches the heat. Don't go faster than the the speed in which the area which has just been exposed to the heat turns colour. When the rim is over the heat, shift along the rim and then continue slowly until the center is back over the heat. Do this steadily until the entire wok has turned. This is the point you start with the oil.
Fold some paper toweling or cloth into a tight wad. Pour a quarter teaspoon of peanut oil on the towel and smear it across the surface. While the heat is still on full, rub the towel around the wok, covering the entire surface quickly and smoothly and rubbing the oil into the steel as if polishing a car. You only want the thinnest possible coating of oil, which, if you're doing this correctly, should start smoking immediately. It will not flame, but it will get very smoky.
If the oil starts pooling or beading, use the towel to soak it back up quickly. Don't let any liquid sit in the pan. You will end up with a gummy residue that is extremely difficult to remove from any surface.
When the smoke has stopped, see if the colour is smooth. If you have lines and dots from oil running down the sides or beading, you didn't clean off all the machine oil or the wok wasn't hot enough. You now have a date with some steel wool. Remove the wok from the heat, douse it with cold water and get scrubbing. Start again.
If the wok's colouring is more or less even, you're in good shape. Slowly move the wok through the heat again so that all parts of the wok are exposed to the intense heat. Then it's time for the oil again. If you like, you can grind a couple turns of pepper into the wok as you run the towel through for what some consider extra flavour, quality and hardness. However, it's not necessary and the resulting smoke is something you don't want to inhale.
You don't need to let the wok cool between oil wipes. Just make sure the thinnest possible film of oil is in there and let the wok "burn" for a few minutes before the next application. Repeat three to five times. Afterwards, turn off the heat and let the wok cool.
Once the wok is cool, look at the inside surface. It should be a deep brown or black and have a look somewhere between wet and dry. If the wok looks completely dry (flat, matte), repeat the process with one or two more oil rubbings. If it looks wet, you probably oiled it after it was cooling. This is bad idea because the oil will go rancid. Heat it up again.
As you cook with your wok, you'll build up a carbon layer which is an excellent non-stick coating. When washing the wok, wash immediately after serving -- don't let food or sauces sit and dry in it and never soak it. Use a soft dish brush, water and, if absolutely necessary, a few drops of dish soap. After cleaning, don't air-dry the wok; put it back on the flame until it's completely dry.
Another method is to use the oven to heat the wok. Obviously, this won't work with wooden handled woks. This method is OK if you can't get the heat from your stove. After cleaning and drying the wok, you "polish" it with oil on a towel and put it in the oven at the highest setting for twenty to thirty minutes. You have to be much more careful about the oil when using the oven method. Since you won't be standing over the wok the entire time, you won't be able to see if the oil is pooling, cooking out and becoming that awful gum.
Obviously, you don't want to season a Teflon-coated wok -- you'll damage the Teflon. It's also not recommended for aluminium, since the metal reacts differently, doesn't change colour as steel does and doesn't easily take a carbon layer. Stainless steel, although the colour may change, also doesn't take a carbon layer well. Due to the composition of the metal, attempting to season stainless steel may destroy the finish already there. In any case, the hammered mild steel wok is the best selection, and most Asian shops offer true hammered woks in the U.S. and Europe for less than $50/€50.
Once your wok is seasoned, you have a cooking tool which should last the rest of your life. You should be able to cook any Chinese recipe and even many western ones. Cooking with a wok offers a bonus in that food no longer has to be removed from the pan before deglazing and making the sauce.