01 - Combine chicken with soy sauce, Shaoxing wine, cornstarch, and black pepper in a bowl. Mix thoroughly and let marinate for 15 minutes at room temperature.
02 - Whisk together black vinegar, light soy sauce, sugar, cornstarch, water, and sesame oil in a separate bowl until cornstarch dissolves completely. Set aside.
03 - Heat 1½ tbsp oil in a large skillet or wok over medium-high heat. Add eggplant cubes and stir-fry for 5–7 minutes until golden brown and tender throughout. Transfer to a plate and reserve.
04 - Add remaining oil to the skillet. Place marinated chicken in a single layer and stir-fry for 4–5 minutes until browned on all sides and nearly cooked through.
05 - Add garlic, minced ginger, and white parts of scallions to the skillet. Stir-fry for 1 minute until fragrant, being careful not to burn the garlic.
06 - Add red and yellow bell peppers to the wok. Continue stir-frying for 2–3 minutes until peppers are slightly tender but still maintain a crisp texture.
07 - Return cooked eggplant to the wok. Toss all ingredients together to distribute evenly and heat through.
08 - Pour prepared sauce over the stir-fry mixture. Cook for 2–3 minutes, stirring constantly, until sauce thickens and coats all ingredients evenly.
09 - Sprinkle with reserved green parts of scallions. Serve immediately while hot, accompanied by steamed jasmine or brown rice.