01 - In a medium bowl, combine the thinly sliced beef with 1 tablespoon soy sauce, cornstarch, and sesame oil. Mix thoroughly to coat all beef strips. Allow the beef to marinate for 10 minutes at room temperature.
02 - While the beef marinates, whisk together all the stir-fry sauce ingredients in a small bowl: 3 tablespoons soy sauce, oyster sauce, rice vinegar, brown sugar, and black pepper. Set this mixture aside.
03 - Heat 1 tablespoon of vegetable oil in a large wok or a spacious skillet over high heat until shimmering. Add the marinated beef in a single layer, ensuring not to overcrowd the pan. Stir-fry for 1 to 2 minutes, just until the beef is lightly browned. Remove the beef from the wok and set it aside on a clean plate.
04 - Add the remaining 1 tablespoon of vegetable oil to the hot wok. Introduce the minced garlic, grated ginger, and sliced scallions. Stir-fry for approximately 30 seconds until the aromatics become fragrant.
05 - Add the thinly sliced green cabbage and julienned carrot to the wok. Continue to stir-fry for 3 to 4 minutes, or until the vegetables are tender-crisp, maintaining a slight bite.
06 - Return the seared beef to the wok with the vegetables. Pour the prepared stir-fry sauce over all ingredients. Toss everything together vigorously for 1 to 2 minutes, ensuring the beef and vegetables are thoroughly coated and heated through. Serve immediately.