Boil a pot of water and cook the lo mein noodles according to package instructions until al dente. Drain and set aside.

In a mixing bowl, combine the sliced beef with cornstarch, a pinch of salt, and pepper to help tenderize the meat.

In a large skillet or wok, heat vegetable oil over medium-high heat. Once hot, add the beef in a single layer and sear for about 2-3 minutes until browned.

Stir in the minced garlic, then add the broccoli florets. Sauté for another 3-4 minutes.

Pour in soy sauce and oyster sauce, mix well, then add beef broth and bring to a gentle simmer.

Toss in the cooked lo mein noodles, ensuring they are well coated with the sauce. Stir-fry for another 2 minutes.

Taste the dish and adjust seasoning with more salt or pepper if needed. Serve hot, garnished with sesame seeds or green onions if desired.