Panda Express is an icon of the American mall food court, feeding families its brand of Chinese American cooking since it first opened in the Glendale Galleria, just outside Los Angeles, in 1983.

Today the chain has more than 2,300 stores, and a big part of that success, is the restaurant’s signature sticky-sweet orange chicken, of which it sells over 110 million pounds per year.

It all begins with the sauce, according to Adrian Lok, the company’s culinary innovation lead, which starts with a thickening starch, along with a mixture of soy sauce, sugar, ginger, and garlic, water, vinegar, and natural orange extract..

“I know it looks like a lot of sugar but it’s for a lot of batches of orange chicken,” says Lok.

Lok says the inspiration for the dish comes from the founders’ home region of Yangzhou, China. “In that region there are a lot of sweet and sour flavors, actually,” he says. “Sometimes it’s misconstrued that sweet and sour is just unique to American Chinese food.”

The chicken gets fried twice before it’s tossed in a wok with the sauce, and finished with a bit of sesame oil. “It’s really good for the aroma of sesame but it also adds a nice shine to the dish as well,” says Lok.

Watch the full video to see how Panda Express makes other iconic dishes like black pepper Angus steak, kung pao chicken, and more.

Pablo Espinosa Gutiérrez