Marinate the Beef: In a medium bowl, combine the thinly sliced beef with 1 tbsp of light soy sauce, the cornflour, and black pepper. Toss well to coat every piece. Set it aside to marinate for at least 10 minutes while you prepare everything else.

Mix the Sauce: In a small bowl or jug, whisk together all the sauce ingredients: light soy sauce, dark soy sauce, oyster sauce, sesame oil, sugar, and stock. Set aside.

Cook the Noodles: Bring a large pot of water to a boil. Add the egg noodles and cook according to the package instructions, usually for about 4-5 minutes. They should be al dente (still have a slight bite). Drain immediately in a colander and rinse with cold water to stop them from cooking and sticking together.

Sear the Beef: Heat 1 tablespoon of oil in a large frying pan or wok over a high heat until it's almost smoking. Add the beef in a single layer (cook in two batches if necessary to avoid overcrowding) and stir-fry for 1-2 minutes until it's just browned but still pink inside. Remove the beef from the pan and set it aside.

Sauté the Vegetables: Add the remaining tablespoon of oil to the same pan. Add the sliced onion and cook for 2 minutes until it starts to soften. Add the minced garlic and grated ginger and stir-fry for 30 seconds until fragrant.

Add Harder Veggies: Tip in the carrots and the sliced bok choy stems. Stir-fry for 2-3 minutes until they are crisp-tender.

Combine Everything: Add the cooked noodles, bok choy leaves, and the prepared sauce to the pan. Use tongs to toss everything together for about 1-2 minutes, ensuring the noodles are well-coated in the glorious sauce. What works best for me is using two wooden spoons to lift and turn the noodles gently.

Finish and Serve: Return the cooked beef to the pan along with the spring onions. Toss everything for a final minute to heat the beef through. Serve immediately.