Mix chicken, cornstarch and oil in a bowl.
Mix Sauce ingredients in a bowl. OR use 3 tbsp Homemade Stir Fry Sauce + 6 tbsp water.
Just before cooking, soak noodles in hot water per packet directions, then drain. (Note 7)
Heat oil in a wok or large skillet over high heat.
Add garlic and onion, cook for 30 seconds.
Add chicken, cook for 1 minute until it changes colour from pink to white.
Add carrot, Choy Sum stems and capsicum. Cook for 1 minute.
Add mushrooms, cook for 30 seconds.
Add noodles, Choy Sum leaves and Sauce. Toss for 1 minute until leaves have wilted and Sauce has evaporated. Don't toss for more then 1 ½ minutes - noodles may break.
Garnish with sesame seeds and green onions then serve immediately.
