01 - In a bowl, mix 1 tablespoon soy sauce, 1 tablespoon cornstarch, and 1/2 tablespoon grated ginger. Add the sliced beef, toss to coat, and marinate for 10 minutes.
02 - In a separate bowl, whisk together the remaining soy sauce, oyster sauce, rice vinegar, brown sugar, remaining ginger, water, and black pepper to make the stir fry sauce.
03 - Heat 1 tablespoon vegetable oil in a large wok or skillet over high heat. Add the marinated beef and stir fry for 2-3 minutes until browned but not overcooked. Remove beef and set aside.
04 - Add remaining oil to the pan. Stir fry broccoli, onion, carrot (if using), and garlic for 3-4 minutes until vegetables are just tender but still crisp.
05 - Return the beef to the pan. Pour in the stir fry sauce and stir to combine. Cook for another 2-3 minutes until the sauce thickens and everything is heated through.
06 - Drizzle with sesame oil, toss, and serve immediately over steamed rice or noodles if desired.