Begin by cutting 1 pound of chicken breast into bite-sized pieces. In a bowl, combine the chicken with 2 tablespoons of soy sauce and 1 tablespoon of cornstarch, mixing until well-coated. Allow the chicken to marinate for about 10 minutes.

In a large pot, bring water to a boil over high heat. Cook the fresh or dried egg noodles according to package instructions, typically around 3-5 minutes for fresh noodles. Once cooked, drain the noodles and rinse them under cold water to prevent sticking.

Heat 2 tablespoons of oil in a wok or large skillet over medium-high heat. Add the marinated chicken in a single layer and cook for about 5-7 minutes until it turns golden brown and is cooked through. Remove the chicken from the pan and set it aside.

In the same pan, add a small splash more oil if necessary, along with 2 minced garlic cloves and 1 tablespoon of minced ginger. Stir-fry over medium-high heat for about 30 seconds until fragrant, then add chopped vegetables. Cook for 3–4 minutes until veggies are bright and tender-crisp.

Return the cooked chicken to the pan with the stir-fried vegetables. Add the prepared noodles and pour in 3 tablespoons of oyster sauce, 1 tablespoon of toasted sesame oil, and a sprinkling of red pepper flakes for heat. Toss everything together quickly over high heat for 2-3 minutes.

Once everything is well combined and heated through, remove the pan from heat. Garnish the stir fry with sesame seeds and sliced green onions. Serve immediately in bowls and enjoy!