1️⃣ Marinate the Beef:

1. In a bowl, mix the sliced beef with soy sauce, cornstarch, and a pinch of black pepper. Let it marinate for 10-15 minutes.

2️⃣ Prepare the Sauce:

1. In a small bowl, combine oyster sauce, hoisin sauce, dark soy sauce, sugar, and 2 tbsp water. Stir well and set aside.

3️⃣ Sear the Beef:

1. Heat 1 tbsp of vegetable oil in a large skillet or wok over high heat.
2. Add the marinated beef in batches and sear for 1-2 minutes per side until browned. Remove and set aside.

4️⃣ Stir-Fry the Aromatics:

1. In the same skillet, heat the remaining 1 tbsp of oil.
2. Add the minced garlic, ginger, and red chilies. Stir-fry for 30 seconds until fragrant.

5️⃣ Add Onions:

1. Toss in the onion wedges and stir-fry for 2 minutes until they begin to soften but still have a crunch.

6️⃣ Combine Everything:

1. Return the seared beef to the skillet.
2. Pour the prepared sauce over the beef and onions. Stir-fry for 2-3 minutes until the beef is evenly coated and the sauce thickens.

7️⃣ Finish with Green Onions:

1. Add the sliced green onions and give it a quick toss.

8️⃣ Serve:

1. Transfer the stir-fried beef to a serving plate. Pair with steamed rice or noodles to soak up the flavorful sauce.