- Stir together the marinade ingredients until the cornstarch is dissolved. Stir the beef in the marinade until coated and let stand for 10 minutes.
- Meanwhile prepare the sauce. Stir together the stock, oyster sauce, rice wine, and soy sauce together in a bowl.
- Cook the broccoli in a small pot of boiling water about 2 -3 minutes. Drain thoroughly.
- Heat a wok over high and add the oil, swirling to coat the sides of the wok. Add beef and cook until no longer pink, about 1 1/2 - 2 minutes. Add the sauce and broccoli and bring to a boil. Pou in the dissolved cornstarch and cook until the sauce boils and thickens, about 1 minute. Serve.