Roast the Peanuts (Optional): Heat 1 teaspoon of oil in a wok over medium heat. Add the peanuts and stir constantly for 3 minutes. Turn off the heat and stir for another minute. Set aside to cool. (Skip this step if using pre-roasted peanuts.)
Marinate the Chicken: In a bowl, mix the chicken cubes with 1 teaspoon oil, cornstarch, Shaoxing wine, salt, and white pepper. Let it marinate for 20 minutes.
Prepare the Sauce: In a separate bowl, mix light soy sauce, dark soy sauce, rice wine vinegar, sugar, water, and cornstarch. Stir well and set aside.
Cook the Chicken: Heat 2 tablespoons of oil in a wok over high heat. Add the marinated chicken and sear until lightly browned. Remove and set aside.
Sauté Aromatics: Reduce the heat to low and add 1 tablespoon of oil. Stir in garlic, ginger, dried chilies, Sichuan peppercorn powder, and scallions. Cook until fragrant, about 1-2 minutes.
Combine Ingredients: Return the cooked chicken to the wok and increase the heat to high. Stir-fry for 1 minute.
Add Sauce: Stir the sauce mixture to ensure the cornstarch is fully incorporated, then pour it into the wok. Stir-fry for another minute until the sauce thickens.
Finish with Peanuts: Add the roasted peanuts, stir everything together, and serve immediately. Enjoy!