Velvet the chicken: Combine sliced chicken with water, Shaoxing wine, salt, and baking soda in a bowl. Massage until liquid absorbs. Add 1 tablespoon cornstarch and mix until coated, then add 1 tablespoon oil. Marinate for 15 minutes.
Prepare sauce: Whisk together soy sauce, chicken broth, brown sugar, remaining 1 tablespoon cornstarch, sesame oil, and chicken bouillon powder if using. Set aside.
Blanch vegetables: Bring a large pot of water to boil. Add broccoli and carrots, cook for 2 minutes. Add bell peppers and mushrooms, cook 1 minute. Add snow peas for 30 seconds. Drain immediately.
Cook chicken: Heat wok or large skillet over high heat until smoking. Add 2 tablespoons oil and swirl. Add chicken in single layer, let sit 1 minute, then stir fry for 2 to 3 minutes until cooked through. Transfer to plate.
Build the sauce: Reduce heat to medium. Add garlic and ginger, stir constantly for 30 seconds until fragrant. Stir sauce mixture and pour into wok. Cook, stirring constantly, for 1 to 2 minutes until thickened and glossy.
Combine and serve: Return chicken and add blanched vegetables to wok. Toss over low heat for 1 minute until everything is coated. Serve immediately over rice or noodles.
