Combine diced chicken with soy sauce, cornstarch, and Shaoxing wine. Mix well and marinate for at least 10 minutes, up to 30 minutes.

Mix the sauce: combine soy sauce, black vinegar, sugar, dark soy sauce, sesame oil, and the cornstarch slurry in a bowl. Set aside.

Heat oil in a wok over high heat until smoking. Add the chicken in a single layer and sear for 2 minutes without stirring, then flip and cook another minute until golden. Transfer to a plate.

Reduce heat to medium. Add Sichuan peppercorns and dried chilies to the wok, stir-frying for 30 seconds until fragrant and the chilies darken. Add garlic and ginger, stir for 10 seconds.

Return chicken to the wok, increase heat to high. Pour in the sauce and toss vigorously until the sauce thickens and glazes the chicken, about 30 seconds.

Add scallions and peanuts, toss a few times to combine. Serve immediately over steamed rice.