This story was produced by Grist and co-published with Eater.
The first thing you notice walking up to a dai pai dong, one of Hong Kong’s signature open-air street food stalls, is the smoke. Aromatic plumes billow out from aluminum-covered vent hoods as chefs with decades of experience produce steaming plates of crackled shrimp, juicy mussels, and crisped-up rice by tossing the ingredients in a giant, flame-cradled wok. As a foodie and avid stir-fry consumer, I love everything involved in wok cooking — the artistry, the bursts of orange under the deep, round-bottomed pan, the incomparable taste. But as a climate reporter, I see just one problem: It typically relies on gas stoves, which release planet-warming methane even when turned off.
Climate experts say that we need to phase out fossil fuel use to address the climate crisis, especially in buildings, which account for 35 percent of U.S. greenhouse gas emissions. Gas stoves also produce harmful air pollutants like carbon monoxide, nitrogen dioxide, and benzene, a known carcinogen.
So when I heard that an all-electric food hall on Microsoft’s campus in Redmond, Washington, featured a pair of custom-made induction woks, I was eager to try out a climate-friendly stir-fry. Unlike gas stoves, induction ranges use electromagnetic currents to heat food, eliminating both the carbon emissions and harmful air pollutants produced by gas. Yet minutes into my lunch with a friend who works at Microsoft, my excitement dissolved. My tofu noodles arrived limp and drowning in vegetable oil.
As I poked at my soggy introduction to induction wok fare, I couldn’t help but think back to a plate of noodles I had eaten at a dai pai dong in Hong Kong just a few weeks before. The two noodle dishes could not have been more different. One was prepared with state-of-the-art climate tech — yet produced lukewarm results. The other was freshly tossed in a kerosene-fueled wok, yielding glossy, chewy noodles bursting with soy sauce, blackened slivers of onion, and, most importantly, that elusive, umami-filled char called wok hei.
Wok hei, loosely translated from Cantonese as the “breath of the wok,” represents the pinnacle of the stir-fry cooking technique most commonly associated with southern China. For all its coveted glory, wok hei — and the question of what exactly produces it — remains somewhat mysterious. The term itself is fairly abstract: while wok refers to the cooking vessel, hei can simultaneously mean “air,” “breath,” “energy,” and “spirit,” leaving room for a variety of interpretations.
Many chefs say that fire, and therefore a gas stove, is essential for achieving the aroma, putting it at odds with climate-driven legal trends: Since 2019, more than a hundred local governments across the United States have introduced policies to ban the use of natural gas in buildings, including gas stoves. Others argue that with high enough temperatures and a few adjustments, chefs can switch to induction and still produce foods with wok hei.
In the face of this gastronomic debate, many chefs are asking what an all-electric future will mean for cherished culinary traditions like wok cooking. When the city of Berkeley, California, enacted its local gas ban in 2019, the California Restaurant Association sued, arguing that gas is essential for certain specialty techniques, including “the use of intense heat from a flame under a wok.” It wasn’t the only attempt to derail gas bans. An investigation by the Sacramento Bee, for example, revealed that the gas utility SoCalGas actively recruited Chinese American restaurant owners to advocate against electrification policies in Southern California.
It would be naive to say gas utility companies were driven by a love of great stir-fry when they turned their lobbying efforts toward wok-based cooking. But the culinary debate around whether wok hei can be achieved over an induction stove has certainly added fuel to the electrification debate.
For chefs, the most important consideration when it comes to switching off gas is whether induction can support their livelihoods. In cities like San Francisco and Los Angeles, some restaurant owners serving Chinese, Thai, and other Asian cuisines using woks have expressed concerns that local gas bans could jeopardize signature tastes and textures.
Whether individual chefs think that induction can achieve wok hei depends largely on how they define it. Wok cooking expert and food writer J. Kenji López-Alt, for example, defines wok hei as a quintessential smoky flavor. He told Grist that it’s impossible to achieve wok hei without gas or fire — and the reason comes down to the food science.
A number of different elements go into that signature smoky aroma, according to López-Alt. One is the flavor imparted from hot, well-seasoned carbon steel or cast iron, two of the most common materials used to make woks. Another component is the caramelization that happens when sauce hits a searing hot pan. If you “watch a Chinese chef cooking, when they add soy sauce to a stir-fry, they swirl it around the outside of the pan where it immediately sizzles and gets intense heat, and that changes the flavor and gives it a bit of smokiness,” he said.
But the main flavor component flavor of wok hei, López-Alt says, comes from the igniting of aerosolized oil with fire. As chefs toss food up into the flames of a gas stove, tiny droplets of fat suspended in the air catch on fire, dripping back down into the wok to impart a subtle smokiness. “You can’t get that without an actual fire,” he said.
Induction stoves, which can instantly heat to temperatures of up to 643 degrees Fahrenheit, are capable of the intensity Yan describes as necessary for wok hei. Yet some chefs like López-Alt say that the shape of the wok presents another obstacle to using induction. Woks feature a deep, high-walled bowl, which allows flames to curl around the vessel and create varied temperature zones — ideal for moving sauces and ingredients around to optimize flavors and control heat. But induction stoves are typically flat and only activate when directly in contact with the pan’s surface.
Lifting the wok to toss ingredients, therefore, would result in an instant loss of heating. Jon Kung, a Detroit-based chef and TikTok personality who advocates for induction cooking, says that induction stoves designed specifically for woks can help with this issue. Like Yan, he defines wok hei as a “mix of char and caramelization” as a result of the Maillard reaction, requiring high heat rather than flames. Kung owns two portable induction wok burners that feature a curved heating area designed to mimic the shape of a traditional wok.
