Stir frying with Wok Hei
Wok hei, a Cantonese phrase that literally means ‘the wok’s breath’, describes the smoky taste obtained when food is cooked in a metal wok over very hot fire.
The cook holds the wok in one hand and moves it about vigorously over the strong flames. Sometimes, this is done in combination with vigorous spatula action to move the food to the edge of the wok and tossing the food in the air by flicking the wok. The food will also catch some of the leaping flames directly, adding to the smokiness of the food. Mostly, it is about using high heat and a thin wok or one made of metal which is a good conductor to transfer heat to the food quickly.
It is, of course, not easy to cook this way at home, unless you have an outdoor kitchen with a high heat stove. However, you can still achieve it by using a good wok and cooking in smaller batches. I have made delicious fried rice and Hokkien Mee with wok hei without smoking up my kitchen. With skill and common sense, recipes that demand wok hei can be done well at home.
A two-phase cooking technique may be needed for some fried dishes. Seafood like crabs and prawns may need to be deep fried before being stir fried in a sauce. Seafood needs to be cooked quickly to prevent the meat from flailing – the cooked part of the meat breaking off from the uncooked part – or going mushy. By deep frying first, oil is used to increase the heat to the food to ensure quick and even cooking before it is flavoured with a sauce through stir frying.
Quite apart from the wok hei, a wok is a very good cooking tool. It is easy to cook big batches of vegetables or noodles with it as the large surface area allows for easy movement and good heat contact.