Combine soy sauce, rice wine or sherry and oyster sauce and set aside.
heat oil in large frying pan or wok. Add onion for 1 minute then add chicken. Saute for 3 minutes - add garlic - saute - add mushrooms, peas, water chestnuts and mix together well - add chicken stock and let cook for approx 4 minutes.
Add sauce previously combined and stir gogether to coat all vegetables.
mix corn starch and water to a medium paste - make an opening in the centre of the pan and begin mixing the cornstarch (thickener) into the sauce. Keep stirring until thicker and everything is coated.
Serve on a bed of rice vermicelli or heated sprouts for a low carb meal. On rice for non low carbers.