To marinate the chicken, in a bowl, add the chicken and the soy sauce, salt, and white pepper, then mix well. In a small bowl, mix cornstarch and water to form a slurry. Add the egg white and slurry to the chicken, then mix until evenly coated. Let it stand while preparing the remaining components.
To make the sauce, in a small bowl, combine the soy sauce, dark soy sauce, Shaoxing wine, Chinkiang vinegar, red chili oil, sugar, salt, and white pepper. In a separate small bowl, mix the cornstarch and water, then stir it into the sauce mixture. Set aside.
To toast the peanuts, in a wok over medium-low heat, add 2 tablespoons of the cooking oil. Add the peanuts and cook for about 3 minutes until lightly browned and fragrant. Remove and set aside the peanuts. Leave the hot oil in the wok.
To infuse the oil, in the same wok over low heat, add the Sichuan peppercorns and cook for about 30 seconds until fragrant. Remove and discard the peppercorns, leaving the infused oil in the wok.
To stir-fry the aromatics, in the wok over medium heat, add the dried red chilies, ginger, garlic, and scallions. Stir-fry for about 30 seconds until aromatic but not browned. Remove the aromatics, leaving the oil in the wok.
To cook the chicken, increase the heat to high until the wok is lightly smoking. Add the remaining 2 tablespoons of cooking oil, then immediately add the marinated chicken. Stir-fry for about 3 minutes until fully cooked through.
To combine and finish, return the aromatics to the wok and give the sauce a quick stir before pouring it in. Stir-fry quickly until the sauce thickens and coats the chicken evenly. Add the toasted peanuts and toss everything together. Serve immediately while hot.
