Bring a large pot of salted water to a boil. Add the dried chow mein/egg noodles and cook according to package instructions until just al dente (usually 3–5 minutes). Drain and rinse briefly under cold water to stop cooking. Toss with 1 teaspoon vegetable oil to prevent sticking and set aside.

Make sauce

In a small bowl whisk together light soy sauce, dark soy sauce (if using), oyster sauce, sesame oil, vegetable broth (or water), white/black pepper, salt and the cornstarch (if using). Stir until cornstarch is fully dissolved. Set aside.

Cook aromatics and vegetables

Heat a large wok or wide skillet over high heat until very hot. Add 2 tablespoons vegetable oil and swirl. Add minced garlic and ginger and stir-fry 10–15 seconds until fragrant but not browned. Add sliced yellow onion and carrot; stir-fry 1–2 minutes until onions begin to soften. Add cabbage and red bell pepper; continue to stir-fry 2–3 minutes until cabbage begins to wilt but remains crisp-tender. Add baby corn (if using) and bean sprouts; toss for another 30–45 seconds. Vegetables should be cooked but still have some bite.

Combine noodles and sauce

Push vegetables to one side of the wok or create a well in the center. Add the cooked noodles and pour the prepared sauce over them. Using tongs or two spatulas, toss everything together vigorously for 1–2 minutes so the sauce evenly coats the noodles and vegetables and the noodles finish cooking and absorb flavors. If mixture looks dry, add an extra tablespoon of vegetable broth or water as needed.

Finish and serve

Taste and adjust seasoning with a pinch more salt or soy sauce if needed. Sprinkle sliced green onions over the top and drizzle with the remaining 1 teaspoon sesame oil if you want extra aroma. Toss once more and remove from heat. Serve immediately, garnished with additional green onions or a squeeze of lime if desired.