Prepare the Steak: In a medium bowl, combine the sliced steak with soy sauce, Shaoxing wine, cornstarch, sesame oil, and baking soda (if using). Mix well and let marinate for at least 30 minutes, or up to 2 hours in the refrigerator.

Prepare the Sauce: In a small bowl, whisk together soy sauce, oyster sauce, brown sugar, Shaoxing wine, sesame oil, and white pepper. Set aside. In a separate small bowl, whisk together beef broth and cornstarch until smooth. Set aside.

Stir-fry the Vegetables: Heat 1 tablespoon of vegetable oil in a large wok or skillet over high heat. Add the garlic and ginger and stir-fry for 30 seconds, or until fragrant. Add the bell peppers and onion and stir-fry for 3-4 minutes, or until slightly softened but still crisp. Remove the vegetables from the wok and set aside.

Cook the Steak: Add the remaining 1 tablespoon of vegetable oil to the wok. Add the marinated steak and stir-fry for 2-3 minutes, or until browned but not fully cooked through. Remove the steak from the wok and set aside.

Combine and Thicken: Pour the beef broth mixture into the wok and bring to a simmer, stirring constantly, until the sauce begins to thicken. Add the soy sauce mixture and stir to combine.

Finish the Dish: Add the cooked steak and vegetables back to the wok. Stir-fry for 1-2 minutes, or until the steak is cooked to your desired doneness and the sauce has thickened to your liking.

Serve: Serve immediately over rice or noodles. Garnish with sesame seeds or chopped green onions, if desired.