Cook Lo Mein noodles according to package directions. Drain and rinse with cold water to prevent sticking. Set aside.
In a small bowl, whisk together soy sauce, oyster sauce, sesame oil, cornstarch, and water for the sauce. Set aside.
Heat 1 tablespoon of oil in a large skillet or wok over medium-high heat. Add minced garlic and ginger and stir-fry until fragrant, about 30 seconds.
Add broccoli florets and carrot to the skillet. Stir-fry for 2-3 minutes until slightly tender-crisp.
Add bell pepper and snap peas to the skillet. Stir-fry for another 2 minutes.
If using chicken, add the cooked chicken to the skillet. Stir to combine with the vegetables.
Pour the prepared sauce over the vegetables and protein. Stir well to coat everything. Cook for 1-2 minutes until the sauce thickens.
Add the cooked Lo Mein noodles to the skillet. Toss gently to combine the noodles with the sauce and vegetables. Cook for another 1-2 minutes until the noodles are heated through.
Serve immediately. Garnish with sesame seeds or chopped green onions if desired.
Notes
This recipe can be customized with your favorite vegetables and protein. For a spicier dish, add a pinch of red pepper flakes to the sauce.