In a bowl, mix soy sauce, oyster sauce, hoisin sauce, cornstarch, and beef broth. Set aside.
Heat vegetable oil in a wok or large skillet over medium-high heat. Add beef and cook until browned, about 3-4 minutes. Remove beef from the pan and set aside.
In the same pan, add the onion, garlic, and ginger. Stir-fry for 2-3 minutes until fragrant.
Add the bell pepper and cook for another 2 minutes.
Return the beef to the pan and pour the sauce mixture over the beef and vegetables. Stir well to combine and cook for another 2-3 minutes until the sauce thickens.
Season with salt and pepper to taste.
Garnish with green onions and serve hot with steamed rice.