Wok

A wok is a deep, round-bottomed cooking pan whose origins are debated: it may have developed independently in China or been adapted from the South Asian karahi. Common throughout Greater China, similar pans appear across East, South, and Southeast Asia, and have gained popularity worldwide. The wok is used for many Chinese cooking methods, such as stir frying, steaming, pan frying, deep frying, poaching, boiling, braising, searing, stewing, making soup, smoking, and roasting nuts. Wok cooking typically employs long-handled spatulas (chǎn) or ladles (sháo) to protect cooks from high heat. A distinctive feature of wok cuisine is the Cantonese concept of *wok hei*, or "breath of the wok."

The wok's exact origin is unclear. One theory holds that it evolved from ancient Chinese cooking pots dating back at least 3,000 years, possibly from a prehistoric round-bottomed pot called the *fu*. Another theory suggests it came from the South Asian *karahi* or the Southeast Asian *kuali* (which may be the root of the Mandarin word *huò*). These vessels were common in South and Southeast Asian cooking for stewing and rapid evaporation, and likely entered China via Central Asia from India, evolving into the wok. In his 1988 book *The Food of China*, E.N. Anderson notes that "wok" is a Cantonese word (Mandarin: *guō*), and that the wok appears to be a relatively recent addition to Chinese kitchens, appearing only about two thousand years ago. The earliest possible depictions are small clay models found on pottery stove models in Han Dynasty tombs, though these were used for drying grains, not cooking. Metal woks did not appear until the Ming dynasty (1368–1644), when they were first used for stir frying, a Han Chinese innovation.

The wok's most defining characteristic is its shape. Classic woks have a rounded bottom. Hand-hammered woks are sometimes flipped inside out after shaping, giving them a gentle flare that makes it easier to push food up the sides. In Western countries, flat-bottomed woks are common, as they work on electric stoves where a round bottom would not make full contact with the heating element. A round-bottom wok allows a traditional round spatula or ladle to scoop up all the food at the bottom and toss it easily—a task that is difficult with a flat bottom. On a gas hob or traditional pit stove, a round-bottom wok can get hotter than a flat one, making it better for stir frying. Most woks range from 300 to 360 mm (12 to 14 inches) in diameter, with 360 mm (14 inches) being the most common size for a family of three or four. Smaller woks (as small as 200 mm or 8 inches) are used for quick, high-heat techniques like stir frying, while larger woks—over a meter wide—are mainly used in restaurants or community kitchens for cooking rice, soup, or boiling water.

The most common materials for woks today are carbon steel and cast iron. Cast iron was historically the most common, but cooks are divided on which is superior. Carbon steel is currently the most widely used material because it is relatively inexpensive, lightweight, heats quickly due to its low specific heat capacity, and is reasonably durable. Its light weight makes it easier to lift and heat faster. However, carbon steel woks are harder to season than cast iron ones (seasoning—carbonizing the cooking surface—prevents sticking and removes metallic tastes and odors). Carbon steel woks vary widely in price, style, and quality, depending on ply and forming technique. The lowest quality are machine-stamped from a single piece of steel; they tend to deform and develop "hot spots." Higher-quality mass-produced woks are made of heavy gauge steel (14-gauge or thicker) and are either machine-hammered or spun. The best woks are almost always handmade, pounded into shape from two or more sheets of carbon steel through a ring-forming or hand-forging process.

Two types of cast iron woks exist. Chinese-made cast iron woks are very thin (about 3 mm or 0.12 inches), weighing only slightly more than a carbon steel wok of similar size. Western-style cast iron woks are much thicker (about 9 mm or 0.35 inches) and very heavy, taking longer to heat up and making stir-frying and *bao* techniques difficult. Cast iron woks form a more stable carbonized seasoning layer, which makes them less prone to sticking.