Marinate the beef:

Stir together the beef marinade ingredients (1 teaspoon soy sauce, 1 teaspoon Chinese rice wine, 1/2 teaspoon cornstarch, 1/8 teaspoon black pepper) in a medium bowl.

Add the beef slices and stir until coated. Let stand for 10 minutes.

Prepare the sauce:

Stir together the sauce ingredients (2 tablespoons oyster sauce, 1 teaspoon Chinese rice wine, 1 teaspoon soy sauce, 1/4 cup chicken broth) in a small bowl. Set aside.

Blanch or steam the broccoli:

Bring a pot of water to a boil. Add the broccoli and cook until crisp-tender, about 2 minutes. Drain thoroughly.

Stir-fry the beef:

Heat a large frying pan or wok over high heat until a bead of water sizzles and instantly evaporates upon contact. Add the cooking oil and swirl to coat.

Add the beef and immediately spread it out all over the surface of the wok or pan in a single layer (preferably not touching).

Let the beef fry undisturbed for 1 minute. Flip the beef slices over, add the garlic to the pan, and fry for an additional 30 seconds to 1 minute until no longer pink.

Add the sauce, cornstarch, and broccoli:

Pour in the sauce and the cornstarch slurry (1 teaspoon cornstarch dissolved in 1 tablespoon of water). Stir until the sauce boils and thickens, about 30 seconds. Stir in the broccoli.

Serve immediately, with steamed rice or on its own.