
This beef stir-fry is fast, savory, and packed with crisp-tender vegetables in a glossy soy-oyster sauce. Marinating the beef keeps it juicy and tender, while high-heat cooking gives the dish classic wok-style flavor. It is an easy dinner for busy weeknights that still tastes restaurant-worthy.
In a bowl, combine the flank steak with the cornstarch, neutral oil, water, oyster sauce, and baking soda. Toss until every piece is evenly coated, then let the beef marinate for at least 30 minutes.
While the beef marinates, wash and prepare the vegetables. Cut the bok choy into bite-size pieces, trim the mushrooms if needed, and have the snap peas ready so everything can go into the wok quickly.
Make the sauce in a small bowl by stirring together the warm water, sesame oil, light soy sauce, dark soy sauce, and sugar until the sugar dissolves.
Heat a wok or large skillet over high heat until very hot. Add a little oil, spread the beef into a single layer, and sear for about 1 minute total, turning once, until the outside is browned but the center is still slightly pink. Transfer the beef to a plate.
Add a little more oil to the wok if needed. Stir-fry the ginger for about 10 seconds, then add the garlic and cook just until fragrant. Add the mushrooms and stir-fry briefly until lightly seared, then pour in the Shaoxing wine.
Add the snap peas and bok choy. Stir-fry over high heat for 1 to 2 minutes, until the bok choy starts to wilt but the vegetables still look vibrant.
Pour in the prepared sauce and return the beef to the wok. Toss everything together over high heat until the sauce comes to a simmer and lightly coats the beef and vegetables.
Keep stir-frying for another 20 to 30 seconds, just until the beef is cooked through and the sauce clings to the ingredients. Remove from the heat and serve immediately.
Slice the beef thinly against the grain for the most tender texture. If you cannot find beech mushrooms, use shiitake or white mushrooms instead, and snow peas work well in place of snap peas. Do not overcrowd the pan, or the beef will steam instead of sear. Leftovers keep well in the refrigerator for up to 2 days.




