In a bowl, mix sliced steak with soy sauce and cornstarch. Let it marinate for 10 minutes.
Heat 1 tbsp oil in a large skillet over medium-high heat. Add steak and sear until browned. Remove and set aside.
Add remaining oil to the skillet. Stir-fry bell peppers, onion, garlic, and ginger for 2 minutes.
Return the beef to the skillet. Add beef broth, oyster sauce, hoisin sauce, sugar, and black pepper. Stir well.
Simmer for 2-3 minutes until sauce thickens.
Serve hot over cooked rice.