Preparation
Combine all sauce ingredients in a saucepan. Bring to boil with constant stirring until the sauce thickens. Set aside.
Heat oil in a large frying pan or a wok; sauté garlic and ginger until fragrant then add the chicken and stir until chicken is changed in color.
Add mushrooms and onion; Stir for 2 minutes.
Fold the boiling sauce on top of the chicken mixture and bring to boil for 1 minute.