1 lb (450g) beef sirloin or flank steak, thinly sliced against the grain
2 tbsp soy sauce
1 tbsp oyster sauce
1 tbsp cornstarch
2 tbsp vegetable oil (divided)
1 red bell pepper, sliced
1 green bell pepper, sliced
1 small onion, sliced
2 garlic cloves, minced
1 tsp fresh ginger, minced
¼ cup beef broth (or water)
1 tbsp brown sugar
1 tbsp rice vinegar (optional for tang)
1 tsp sesame oil
Salt & black pepper to taste
Sesame seeds and green onions (for garnish)
Instructions
Marinate the Beef:
In a bowl, combine sliced beef with soy sauce, oyster sauce, and cornstarch. Mix well and let it marinate for 10–15 minutes.
Cook the Beef:
Heat 1 tbsp oil in a large skillet or wok over high heat. Add the beef in a single layer and stir-fry until browned (about 2–3 minutes). Remove from pan and set aside.
Stir-Fry Veggies:
Add another 1 tbsp oil to the same pan. Add garlic, ginger, onions, and bell peppers. Stir-fry for about 3–4 minutes until crisp-tender.
Make the Sauce:
In a small bowl, mix beef broth, brown sugar, rice vinegar, and sesame oil. Pour into the pan.
Combine & Finish:
Return beef to the pan, toss everything together, and cook for 2–3 more minutes until the sauce thickens slightly.
Serve:
Garnish with sesame seeds and green onions. Serve hot over steamed rice or cauliflower rice for a low-carb version.
Tips & Variations
Add mushrooms or snow peas for extra crunch.
Use low-sodium soy sauce to control saltiness.
For a spicier version, add crushed red chili flakes or sliced chili peppers.