In a medium bowl, combine the sliced chicken, 1 tablespoon of soy sauce, cornstarch, and Shaoxing wine. Mix well until every piece is coated. Set aside to marinate for at least 15 minutes.

In a separate small bowl, whisk together all the stir-fry sauce ingredients: oyster sauce, 2 tablespoons of soy sauce, dark soy sauce, black pepper, brown sugar, sesame oil, and chicken broth. Set aside.

Heat 1 tablespoon of oil in a large skillet or wok over medium-high heat. Once shimmering, add the chicken in a single layer. Cook for 2-3 minutes per side, until golden brown and cooked through. Remove the chicken from the wok and set it aside.

Add the remaining tablespoon of oil to the wok. Add the diced onion and celery and stir-fry for 3-4 minutes until they begin to soften. Add the minced garlic and grated ginger and cook for another minute until fragrant.

Return the cooked chicken to the wok. Pour the prepared stir-fry sauce over everything. Stir well to coat, bringing the sauce to a simmer. Let it bubble for 1-2 minutes, allowing the sauce to thicken and cling to the chicken and vegetables.

Serve your delicious Black Pepper Chicken hot over a bed of steamed rice or noodles.