Wok Skills 101: Stir-Frying

“Stir-frying” is arguably the most well-known technique in wok cooking—both within China and across the globe. But contrary to what some may practice, the method is a little more nuanced than tossing some meat and vegetables around in a wok, drowning them in soy sauce, and calling it a day. Stir-frying in a wok has a long history that traces back thousands of years, but only in the last few centuries has it developed into the technique that we know now. Let’s dig in.

Where Did Stir-Frying Come From?

The earliest evidence of the origins of the “stir-fry” technique comes from bronze inscriptions found on pots and cauldrons from the Eastern Zhou period (771-256 BC) in China, upon which the character “炒” (ch’ao; pinyin: chǎo) appears. Here, chao refers to “dry stirring,” indicative of the method used to dry grain in a wok. It wasn’t until the 6th century AD that “chao” was used more in line with the modern stir-frying technique, in the agricultural text Qimin Yaoshu's recipe for scrambled eggs. "Chao" continued to appear sporadically in texts for the next several centuries, flipping back and forth between the two meanings of either a drying technique or a cooking method.

By the late Ming Dynasty (mid 1600s), as the cost of inputs like wood and charcoal increased, the popularity of stir-frying grew, since it became an efficient way to cook food quickly without wasting fuel. By the late Qing dynasty (1910s), most Chinese homes had a wok range, so stir-frying became a more commonly used method of cooking. Up until this period, though, boiling, braising, and steaming were far more popular methods of cooking. Cooking fats like lard and oil were expensive and hard to obtain prior to widespread commercial availability.

“Stir-fry” as an English Term

In the late 19th century, as Chinese immigrants established communities across America, stir-frying was a way of providing familiar comfort in unfamiliar land. But “stir-fry” didn’t appear in its English translation until 1945, in Buwei Yang Chao’s How to Cook and Eat in Chinese—considered the first earnest effort toward an English translation of Chinese cooking techniques. On the term chao (炒), Chao writes:

...[it] cannot be accurately translated into English. Roughly speaking, ch'ao may be defined as a big-fire-shallow-fat-continual-stirring-quick-frying of cut-up material with wet seasoning. So we shall call it stir-fry…

By the latter half of the 20th century, as the popularity of Chinese cuisine grew, those outside the Chinese population began to integrate stir-frying into their everyday cooking. But many Americans, both Chinese and non-Chinese, often stir-fry in a skillet, which lacks many of a wok's inherent advantages.

What’s Unique About Stir-Frying In a Wok?

Many home cooks reach for a Western skillet when they want to stir-fry food. Why? Here’s Kenji, in an earlier version of this article, with the main argument for the pro-skillet camp:

I've read in some otherwise reputable sources that using a wok is not the ideal way to stir-fry. Indeed that, on a Western range, using a 12-inch skillet is actually better. I've even seen charts showing how 12-inch skillets get hotter, retain heat better, and have larger surface areas. I've seen how a wok doesn't sit right on a flat range and how it was designed for a much larger flame. All of this is absolutely true.

Kenji goes on, though, to argue that despite these facts, a wok still makes a superior stir-fry. According to Grace Young, “poet laureate of the wok” and award-winning author of Chinese cooking classics like Breath of The Wok and Stir-Frying to the Sky’s Edge, a wok is essential to a proper stir-fry. “A chef once told me, if you stir-fry in a skillet, you’re just chasing the ingredients around the pan,” Young says. A skillet might get hot, but the result is hardly the same; the key difference is in the movement of food and the heat of a wok.  

Overall, the shape and construction of a wok enables rapid, dynamic movement of food through different zones of heat, which makes cooking a wok different than cooking in a skillet in several ways. Let’s take a closer look.

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The Material of The Wok

Woks are generally constructed of thin, conductive metals like carbon steel or cast iron. In contrast to the heavy gauge of Western cast iron or carbon steel skillets, a wok is noticeably lighter. For a 14-inch wok, Young recommends a total weight of three and a half pounds. In fact, in the old days in Chinatowns, Young says, lighter gauge, hand-hammered woks were more common, and you could squeeze the sides between your hands so that they would bend slightly. These days, most woks are a slightly heavier gauge and machine-spun—but still noticeably thinner than Western skillets.

That thinness of the metal means that the wok heats up quickly. Despite being made of steel, which is much less conductive than other culinary metals, like copper or aluminum, a wok's thinness means it's among the most conductive pans you could own. It's highly responsive to the output of the heat source you are using. And when it comes to stir-frying, that responsiveness leads to faster cooking.

The Shape of The Wok

A wok is concave with tall, sloped sides and a relatively small area in direct contact with the heat source.  There’s tons of room to stir and toss food. The unique shape of the wok also leads to distinct zones of heat.

The most common explanation of those heat zones goes as follows: At the bottom, you’ve got the hot, conductive surface that’s constantly in contact with the heat source. If you’re using a high-output burner—especially with a round-bottomed wok—then this conduction zone can be blazing hot—up to 1,500℉ on a professional setup. Just above the conductive zone, there is a condensation or steaming zone. As food is tossed in the wok, it passes through a cooler region of air, and steam condenses on the surface of the food, imparting its energy to the food, which cooks it. Even higher up, you’ve got a convection zone, which is even cooler. The air is drier up there, so heat transfer isn’t as efficient—but food continues to cook slowly and gently as it moves through the space.

Wok Shape + Material = Faster Cooking and Unique Textures

Together, the shape and material of a wok help to cook food quickly as it moves through different heat zones. The constant high heat applied to the thin metal powers this process, and the end result is food that exhibits unique characteristics: seared and hot, but also vibrant, fresh, and evenly cooked. Imagine the benefits of searing, combined with the tender-crisp freshness of blanching or steaming. You can’t really reproduce that exact effect in a standard Western skillet. Finally, stir-frying in a wok is fast. Since a traditional skillet primarily has a single heat zone at the bottom (and a small convection zone above), the rate of cooking is slower overall.

Stir-Frying on a Seasoned Wok Tastes Better

It’s worth noting that a seasoned wok—one that has had many layers of a protective coating of polymerized oil built on top—might also confer some flavor benefits to a stir-fry. Some believe that the polymerized oils on the surface of a seasoned wok add a “roasted” or “caramelized” flavor to the food; or more poetically, that the flavor is a reflection of all the food that has been cooked in the wok previously—a culmination of the wok’s ‘food memories,’ as Grace Young puts it. Whatever the explanation, the seasoning on a wok may be an important X-factor.

A Wok Facilitates Wok Hei

No discussion of stir-frying would be complete without mentioning wok hei, translated as “the breath of the wok” or “wok aroma.” Young defines wok hei as the energy a wok bestows upon a stir-fry, giving foods a unique smoky flavor and aroma. Kenji gets more technical with it, noting that a large portion of wok hei may come from three things:  

1. The intense flavors you get through high-heat cooking, specifically the flavors imparted by the layer of polymerized oils in a well-seasoned wok, and the rapid cooking that the action of constantly tossing food through a cloud of its own steam allows for.
2. The singeing of aerosolized fats, which occurs as flames lick up over the back of the wok as food is tossed; the singed fats fall back into the food.
3. The searing of soy sauce and other liquids added around the perimeter of the wok during the last stages of a stir-fry.

You can even achieve some of the same effects with a kitchen blowtorch, but it’s not quite the same.

Does every stir-fry need to have wok hei? Absolutely not. Many argue that the current cultural obsession with wok hei—particularly outside of China—is overblown. Most home cooks aren’t cooking on huge wok burners, and they’re getting along just fine. As Serious Eats contributor and Chef Lucas Sin of Junzi Kitchen explains, wok hei is really more of a feature of restaurant food. “You’re paying for that flavor,” Sin says. “Why would you go to all that trouble to smoke out your kitchen, when you could go down the street to your local Chinese restaurant and buy that flavor for less than $15? It’s no big deal.”

The Anatomy of a Stir-Fry

Here is the general order of operations for a stir-fry:

1. Heat Wok Following "Hot Wok, Cold Oil"

Unlike many recipes involving Western skillets, a wok stir-fry starts with heating a dry wok until it’s ripping hot. Why? Conventional wisdom says that the surface should be hot before adding oil to optimize the wok’s nonstick properties, improving both the speed and ease of the cooking process. In Chinese cooking, this nonstick feature is the crux of “hot wok, cold oil” (热锅冷油). In Chinese professional kitchens, chefs routinely practice longyau (熱油), which involves swirling a generous amount of room temperature oil in a wok after heating a dry pan, coating nearly the entire surface; they dump this oil out to the side into a dedicated container, then add a smaller amount of oil before continuing the stir-fry. In this video, the legendary Sichuan Chef Wang Gang demonstrates longyau.

At minimum, this concept is a good reminder to season the pan before cooking. “Starting with cold oil in a hot wok ensures that you have this practice of coating your wok in oil,” says Lucas Sin. “You’re reminding yourself to season your wok every time you cook. In my opinion, it also reduces the overall amount of oil you need to use, since you’ve done the work to produce that nonstick property from the start.” 

From a more technical perspective, Kenji argues in his book The Wok: Recipes and Techniques that adding cold oil to a hot wok simply has a flavor benefit, which is far more important:

“I found that whether I heated up the oil with the wok or added oil to an already preheated wok, my food was equally unlikely to stick. But there was one big difference: flavor. With stir- fries, you typically preheat the wok even hotter than you would heat a Western skillet for searing. If you start with oil in a cold wok, by the time it’s hot enough to start cooking, the oil will have already broken down a great deal, producing free radicals and acrolein, which gives stir-fries a burnt, acrid flavor.”

What oil should you use? Any fat with a high smoke point is ideal. Options include peanut oil, canola oil, corn oil, avocado oil, rice bran oil, tea seed oil, grape seed oil, sunflower oil, safflower oil, and animal fats like lard.

2. Add Aromatics

Typical Chinese aromatics include garlic, ginger, and scallions, though they can also include things like fresh chiles, lemongrass, herbs, or preserved and pickled vegetables. As Grace Young points out, this step can be a good indicator of your wok’s temperature. “By the time you add aromatics, you need to hear a sizzle. If there is no sizzle, then you have not heated the wok correctly. I always say to people: your wok is going to be talking to you.”

3. Add Longer-Cooking Ingredients

In most Chinese dishes, either the protein or the vegetables are the star, and the other is used as a flavoring. When the protein is the main element, it is usually marinated or brined before cooking in order to add flavor and moisture. When used as a flavoring, it's most often ground or finely chopped.

On a relatively weak home range, Grace Young recommends spreading meat in a single layer, letting it cook on the first side for one full minute without moving. “It gives a much better flavor than if you added the meat and immediately started stir-frying—you would get more sticking and you would not get the meat to brown,” Young says. She also advises that most home ranges can’t handle more than 1 pound of meat at a time (according to Young, the limit for beef on a 14-inch wok is twelve ounces; any more results in steaming and gray, foamy meat).

Whatever the ingredient, the first components after aromatics are always ingredients that take the longest to cook. If the meat requires extended cooking, it might even be pre-cooked or par-cooked prior to stir-frying. If the vegetables are tough, fibrous, or relatively non-porous (cauliflower or carrots, for example), then pre-blanching may be necessary to ensure even cooking. 

4. Add Shorter-Cooking Ingredients, If Applicable

Quick-cooking foods include vegetables like leafy greens, bean sprouts, or snow peas. The idea here is to cook the food quickly to preserve its vibrancy. In Chinese, the term is to “break the rawness” (duan sheng/断生). These ingredients are cooked but still crisp and fresh, not pallid and sad.

Kenji advises to try to limit your vegetable selection to one or two carefully paired choices—otherwise you end up with what he calls "food court syndrome," where there's so much junk inside that it's impossible to cook any one ingredient perfectly. (And avoid canned baby corn at all costs.)

Further down the ingredient list, we’ve got ingredients that require little to no cooking at all—they’re simply extras. These often include cashews, peanuts, or small chunks of scallion greens (to break their rawness). For nuts, they’re often fried or roasted ahead of time.

5. Add Sauce/Slurry

Once the skeleton of the stir-fry has been built, it’s common to add liquid or sauce to season the mixture. Additions can be as simple as broth or soy sauce, but can also include rice wine, vinegar, sugar, honey, oyster sauce, hoisin sauce, any kind of chile paste, fermented bean paste, fermented tofu—the list is neverending. A key feature here is that the mixture is often thickened slightly with cornstarch, potato starch, or arrowroot starch—products that give an attractive sheen and “slippery” quality to the stir-fry (Hua/滑). 

Chinese-American food tends to be voluminous and thick—people around here like to have enough to put on their rice. In most traditional dishes, the sauce is a little thinner, more strongly flavored, and there's just enough to coat the food. That way, a meal is balanced between the bland rice and the super-flavorful stir-fry.

Finally, it’s important to build whatever sauce mixture you’re using long before you start cooking. “I don’t like keeping bottles of sauce out,” Lucas Sin says. “I tell people to mix the sauce in a bowl before cooking. That way, you don’t have to stop and think.”

6. Add Garnishes

Garnishes include sliced scallions, fried shallots, cilantro, sesame seeds, fried ginger—pretty straightforward. The key here is ingredients that don’t require any cooking.

The Importance of Preparation

Stir-frying happens quickly. "Everything has to be prepped ahead of time," says Young. “There's no last-minute cutting something as you’re stir-frying; you shouldn't be taking a photo for your Instagram post, because this is on high heat, and it requires your full attention.” The key is to prepare both your ingredients and your workspace.

Prepare Your Ingredients

Vegetables

Vegetables should be cut to a uniform size to ensure even cooking. You should select vegetables that are roughly the same size and shape. “You wouldn't be using a really thick asparagus with pencil asparagus,” says Young. You pick one size or the other. Lastly, vegetables should be dry before they hit the wok. Make sure to wash and dry ingredients like leafy greens properly—even letting them air dry—so that they don’t start to steam as soon as cooking begins.   

Meats

In general, meats need to be sliced and marinated before cooking. Like vegetables, the pieces should be roughly the same size.

Pre-Cook Ingredients

Given the speed of stir-frying, many ingredients can’t cook properly without some form of pre-cooking. That means blanching or "passing through" hardy vegetables, or velveting any proteins to the proper texture. 

Prepare Your Workspace

The general setup for stir-frying is optimized for speed and safety. Everything should be within reach. Specifically, you should have:

A Landing Pad

A dedicated area to unload your ingredients is essential, especially if you’re cooking things in batches.

A Sheet Pan or Wire Rack

This could be a space to hold utensils, but also to hold your mise en place and seasonings. A contained, organized space limits mess and streamlines your workflow.

Water Nearby

Water is an underrated but essential ingredient in stir-frying. You can use it to adjust the consistency of a sauce or slurry on the fly. “You might need water to cool down the wok, or add liquid if things are too dry,” says Lucas Sin. Keeping a small cup or bowl of water nearby is a great idea.

A Lid

A lid is an often overlooked tool. It can trap steam to speed up cooking, and it doubles as a safety tool. In the event of unexpected flare ups or—god forbid—a raging grease fire, use it to snuff out the flames immediately.

Ventilation

Unless you’re stir-frying outside, things will inevitably get smoky in your kitchen. And let’s face it: Most of us aren’t blessed with professional kitchen ventilation. So open the windows and get that trusty box fan out.

Tools for Stir-Frying in a Wok

There are certain tools unique to stir-frying in a wok. Here’s a brief overview of what you might use:

Wok Spatula (Chuan)

Also known as a Chinese spatula, this shovel-like utensil is designed to follow the curvature of the wok. It’s thin enough to get under all ingredients, to scoop up and redistribute the food. According to Grace Young, if you can’t find a good wok spatula, a simple thin fish spatula works well as a substitute.

Wooden Spoon/Spatula

Some cooks worry that the sharp edges of a traditional wok spatula can scratch up the surface of a wok. Instead, they opt for a wooden spatula, which is easier on the surface. And though wood is a ‘safer’ option, Young thinks it’s overrated: “Wood is just too thick. So when you're stir-frying something with rice noodles, beef, chicken, you cannot get under it. And so that means you're actually going to start ripping your meat.” Plus, Young doesn’t worry too much about scratching. “The scratches tell a story.” 

Wok Ladle (Hoak)

This is a large, wide ladle with a slight angle from the handle. Often, you see cooks tossing food with one hand as they corral the ingredients using the back of this tool. For those using round-bottomed woks, this motion makes sense: Like the wok spatula, the shape of the wok ladle fits the curvature of the wok.

Hand Skills for Stir-Frying

Stir-frying involves specific hand skills that emphasize the rapid movement of food through different heat zones—all in an effort to regulate heat and maximize flavor

Observe and Regulate Heat

Perhaps the most important skill in stir-frying is learning to control heat. “At home, I just rip it on high heat the whole time,” says Lucas Sin. There’s hardly time to fiddle around with dials—much less on a professional wok burner. So looking for signs of oil shimmering or smoking, observing the temperature of the wok, and knowing when to just take the wok off heat are essential skills that come with experience.

Stirring (shoveling)

“Stirring” in a stir-fry isn’t quite the right term—it’s more like shoveling or flipping. “You want to move the food around, and make sure to flip it every once in a while,” says Sin. Again, don’t just chase the food around the pan.

Wok Tossing/Tumbling

In Chinese culinary school, cooks are taught several methods of wok tumbling or “flips”: There’s the little flip, big flip, medium flip. Due to the physics of a round-bottomed wok, this motion differs from flipping food in a Western skillet. It’s more of a circular pulling motion, says Sin. It’s less of the herky-jerky pushing motion that characterizes the motion in a flat skillet. In fact, if you want a deeper look, here’s a study that painstakingly breaks down the physics of tossing fried rice.

Still, it’s possible to produce the same net effect when using a flat-bottomed wok. “The key is to have the food touch as many parts of the wok as possible,” says Sin. Whatever motion gets you there—it’s better than nothing. 

Sauce Around the Side of the Wok

When adding soy sauce or other mixture to a stir-fry, it’s best to avoid dumping it into the center of the wok. Why? It cools down the center of the wok, resulting in unwanted steam. In his testing, Kenji also found that searing the sauce around the perimeter of the wok contributed to the overall wok hei flavor: “Adding soy sauce to the center of the wok left the noodles with a raw soy sauce flavor, while drizzling it around the hot edges of the wok created smoky flavors reminiscent of grilled meat.”

Stir-Frying Is Elemental

There are few cooking techniques as dynamic and exciting as stir-frying. “Chinese cooking is a cuisine of fire,” says Lucas Sin. And stir-frying in a wok is a perfect demonstration of that idea. The sights, the sounds, and the searing heat give immediate feedback. “You're just more in tune, and it's also your senses,” says Grace Young. “It smells a particular way when it's ready. All of your senses are awakened when you're stir-frying.”