1. Prepare the beef and vegetables. Thinly slice the flank steak or sirloin against the grain. Slice the bell pepper and onion, julienne the carrot, cut the broccoli into small florets, mince the garlic, and grate the ginger.

2. Mix the stir-fry sauce. Combine soy sauce, oyster sauce, hoisin sauce, honey or brown sugar, and 2 tablespoons water in a small bowl. In another cup, mix the cornstarch with the remaining 1 tablespoon water until smooth.

3. Heat a large wok or heavy skillet over high heat. Once hot, add 1 tablespoon vegetable oil.

4. Add the beef in a single layer and sear for 1–2 minutes. Stir briefly until most surfaces change color, then transfer the beef to a clean plate.

5. Add the remaining tablespoon of vegetable oil. Stir in the garlic and ginger for about 10 seconds. Add the onion, red bell pepper, broccoli, and carrot. Stir-fry for 3–4 minutes until colorful and crisp-tender.

6. Return the beef and accumulated juices to the skillet. Pour in the prepared sauce and toss everything together.

7. Stir the cornstarch slurry again and pour it into the skillet. Toss for approximately 1 minute until the sauce bubbles, thickens, and coats the beef and vegetables.

8. Remove the skillet from the heat. Drizzle with sesame oil and toss. Garnish with green onions and toasted sesame seeds, then serve immediately.