Sesame seeds, sliced green onions, and hot rice for serving
Instructions
Marinated Beef
Place beef in a large bowl and add soy sauce, rice wine vinegar, and cornstarch. Toss to evenly combine. Let beef marinade 20 minutes.
Heat oil in a large nonstick skillet or wok over medium-high heat until shimmery. Add beef and let cook undisturbed in a single layer on first side 3-4 minutes, then flip to opposite side and cook an additional 3-4 minutes until beef is golden brown. Transfer beef to a plate and set aside.
Vegetables
Wipe pan clean with paper towels and heat oil over medium-high heat until shimmery. Add onion, beans, and sweet pepper. Saute vegetables 4-6 minutes, stirring occasionally until vegetables are crisp-tender.
Add scallions, ginger, and garlic to vegetables and cook an additional 3-4 minutes until fragrant and vegetables are tender. Remove from heat for a moment.
Sauce
In a small bowl, whisk soy sauce, honey, oyster sauce, rice vinegar, and pepper. In a small separate bowl, whisk cornstarch and water. Whisk into soy sauce mixture until smooth.
Pour sauce over vegetables and add beef. Cook over medium-high heat 3-4 minutes until sauce is slightly thickened and coats vegetables and beef.
Season black pepper beef with salt and additional pepper to taste if desired. Garnish beef with sesame seeds and green onions and serve over hot rice if desired.