Marinate chicken for at least 15 minutes in 2 tsp light soy sauce, shaoxing wine, 2 1/4 tsp cornstarch, 1 tbsp water, salt
Add 2 tbsp oil to wok or cast iron over high heat. When hot but not yet smoking, add chiles and sichuan peppercorns. Stir fry briefly until fragrant
Add chicken, stir frying constantly until barely cooked
Add ginger, garlic, and scallions. Stir fry until tender and fragrant
Give the sauce (sugar, 1 1/8 tsp cornstarch, dark soy sauce, 1 tsp light soy sauce, chianking vinegar, sesame oil, 1 tbsp water) a quick stir and pour it over the wok, stir frying and tossing until sauce is thick and shiny
Stir in peanuts and serve