Prep the Beef: Toss the sliced beef with cornstarch, soy sauce, and a generous amount of freshly ground black pepper.
Cook the Beef: Heat 1 tablespoon of vegetable oil in a skillet or wok over high heat. Quickly stir-fry the beef until browned but not fully cooked. Remove and set aside.
Stir-Fry Veggies: In the same pan, add the remaining oil and stir-fry garlic, onion, bell pepper, and broccoli until just tender-crisp.
Combine & Sauce: Return the beef to the pan, add soy sauce, oyster sauce (if using), and sugar or honey. Toss everything together until coated in a glossy, peppery sauce.
Serve: Serve hot over steamed rice or noodles.
