In a mixing bowl, whisk together the 1 tbsp soy sauce, 1 tsp cornstarch, 1 tsp sesame oil, and 1 tsp Shaoxing rice wine. Add the 1 ½ lb boneless skinless chicken thighs cut into 3/4-inch pieces and toss to coat evenly. Let marinate at room temperature for at least 10 minutes while you prep the remaining ingredients.

In a small mixing bowl, whisk together the 1 tbsp soy sauce, 2 tbsp rice vinegar, 1 tbsp hoisin sauce, 1 tbsp granulated sugar, 1 tsp cornstarch, 1 tsp sesame oil, and 2 tbsp water until the sugar and cornstarch are fully dissolved. Set aside near the stove — the sauce comes together fast once cooking starts.

Heat a wok or skillet over high heat until very hot — a drop of water should evaporate on contact. Add 1 tablespoon of the vegetable oil and swirl to coat. Add the marinated 1 ½ lb boneless skinless chicken thighs cut into 3/4-inch pieces in a single layer and let it sear undisturbed for 90 seconds, then stir-fry until just cooked through, about 2–3 more minutes. Transfer the chicken to a plate and set aside.

Return the wok to high heat and add the remaining 1 tablespoon of vegetable oil. Add the 8 whole dried red chilies such as Tien Tsin or árbol and 1 tsp Sichuan peppercorns lightly crushed (if using) and stir-fry for 20–30 seconds until fragrant and the chilies just begin to darken. Do not let them burn.

Add the 4 cloves garlic minced, 1 tbsp fresh ginger minced, and the white parts of the stalks scallions cut into 1-inch pieces. Stir-fry for another 30 seconds until fragrant.

Add the 2 medium bell peppers red or green and stir-fry for 1–2 minutes until just tender but still slightly crisp.

Return the cooked 1 ½ lb boneless skinless chicken thighs cut into 3/4-inch pieces to the wok. Give the sauce a quick stir (the 1 tsp cornstarch settles), then pour it over everything. Toss and stir-fry for 1–2 minutes until the sauce thickens and coats the chicken and vegetables in a glossy glaze.

Remove from heat and stir in the ¾ cup roasted unsalted peanuts and the green parts of the stalks scallions cut into 1-inch pieces. Serve immediately over steamed white rice.