In a medium-sized bowl, combine the marinade ingredients: soy sauce, Shaoxing wine, cornstarch, and brown sugar. Add the thinly sliced chicken breast to the mixture, ensuring each piece is coated. Let it marinate in the fridge for at least 30 minutes or overnight for the best flavor. If short on time, allow the chicken to marinate while prepping the remaining ingredients.

Step 2: Mix the Sauce

In a small bowl, whisk together chicken stock, soy sauce, oyster sauce, brown sugar, cornstarch, Chinese black vinegar, sesame oil, minced garlic, and grated ginger. Stir well and set aside.

Step 3: Sear the Chicken

Heat a wok or large skillet over high heat. Once hot, add vegetable oil and lay the marinated chicken pieces flat in a single layer. Avoid adding the marinade to the pan. Let the chicken cook undisturbed for 30 seconds to 1 minute until a golden-brown sear forms. Flip the chicken and repeat on the other side. Remove the chicken from the pan and set aside.

Step 4: Cook the Vegetables

Using the same pan, add the sliced mushrooms and zucchini. Saute over medium-high heat for 2-3 minutes until tender but still crisp. Reduce the heat to medium.

Step 5: Combine Everything

Return the chicken to the pan with the vegetables. Stir the sauce to ensure the cornstarch is fully incorporated, then pour it into the pan. Use about half the sauce if you prefer a lighter coating. Stir everything together for 1-2 minutes until the sauce thickens and coats the chicken and vegetables evenly.

Step 6: Garnish and Serve

Transfer the dish to a serving plate and sprinkle sesame seeds on top for garnish. Serve immediately with steamed rice or noodles for a complete meal