The sauce that is on Panda Express beef and broccoli is savory, classic ginger soy sauce.
The savory and classic ginger and soy sauce that Panda Express uses on their Beef and Broccoli is a rich that contains soy source, fresh ginger, garlic as well as often oyster sauce, a thickener like cornstarch and brown sugar, which creates a signature rich, slightly sweet and umami flavor.
The actual recipe for Panda Express ginger soy sauce is not fully known s proprietary, although the core of the Panda Express Ginger soy sauce is a savory, slightly sweet brown sauce that is built on a foundation of soy, ginger and garlic, which creates the familiar Panda Express restaurant taste.
You can make a similar sauce to use on beef and broccoli by using the following ingredients which include.
A base of soy sauce, ginger and garlic.
Brown sugar or sugar for sweetness.
Oyster sauce for Umami and Depth.
Cornstarch or modified food starch for thickener.
Chicken broth or water for the liquid.
And aromatic ingredients like sesame oil and rice vinegar.
To make a similar copycat sauce to the sauce that Panda Express uses on beef and broccoli you start by marinating the beef with soy sauce, Shaoxing wine and sometimes cornstarch to tenderize the beef.
Then you whisk together ingredients like oyster sauce, soy sauce, sugar, broth, rice vinegar and corn starch.
And then the beef is stir fried quickly, then you add the broccoli.
The sauce mixture is then poured in and cooked until it thickens up into a glossy glaze, coating the beef and broccoli.