Heat 2 tablespoons vegetable oil in a wok or large skillet over high heat. Add chicken to the wok, and stir-fry until chicken is opaque on all sides, about 3 minutes. Remove to a plate.
Heat the remaining 1 tablespoon vegetable oil in the wok. Add bell pepper, onion, and snow peas; stir-fry until vegetables start to soften, 3 to 4 minutes. Reduce heat to medium-low.
Whisk together water, hoisin sauce, soy sauce, sherry, ginger, rice vinegar, sesame oil, oyster sauce, sugar, cornstarch, and garlic in a bowl. Add sauce to the wok, stirring constantly until sauce starts to thicken. Add chicken back to the wok, stir, and reheat, 1 to 2 minutes.
Nutritional FactsCalories: 392% Daily Value *Total Fat: 31 %Saturated Fat:Cholesterol: 22 %Sodium: 53 %Potassium: 12 %Carbohydrates: 8 %Fiber: 9 %Sugar:Protein: 53 %Vitamin A Iu:Niacin Equivalents:Vitamin B6:Vitamin C:Folate:Calcium:Iron:Magnesium:Thiamin: