Noodles. Cook the pasta according to the package instructions. Be careful not to overcook them, as they will continue to cook later in the sauce.
Make The Sauce. In a medium-sized bowl, combine all the sauce ingredients. Set aside.
Chicken Marinade. In another medium-sized bowl, place the chicken breasts. Pour 2 tablespoons of the sauce over the chicken, cover with plastic wrap, and let it marinate for at least 1 hour. If you're short on time, you can prepare the marinade the night before and marinate the chicken overnight. Even a shorter marination time will add flavor and tenderness to the chicken.
Cooking the Chicken. Heat 1 tablespoon olive oil in a large skillet (a wok pan is optional) over high heat. Cook the marinated chicken for 3-4 minutes on each side until it turns slightly golden brown. Remove the chicken from the heat and set it aside.
Vegetable Stir-Fry. In the same skillet, add remaining 1 tablespoon olive oil and sauté the mushrooms for 3-4 minutes over medium heat. Then, add the remaining vegetables except green onions (bell peppers, carrots, garlic) and cook until the bell peppers and carrot become tender but not overly soft (about 1-2 minutes).
Bringing It All Together. Reduce the heat to low. Pour the prepared sauce into the skillet, green onions, and simmer until the mixture starts to thicken. Return the cooked chicken and add noodles to the pan. Toss everything together until the noodles are thoroughly coated and slightly browned with the sauce.
Garnish and Serve. Garnish the dish with green onions and sesame seeds. Serve the meal while it's still warm. Enjoy!