1-First Step: Marinate the Chicken
Cut 8 boneless chicken thighs (or 450 grams chicken breast) into bite-size chunks. In a bowl, combine 1 tablespoon dark soy sauce, 1 tablespoon light soy sauce, 1 tablespoon Chinese rice wine, 1/4 teaspoon white pepper, and 2 to 3 tablespoons cornflour. Add the chicken pieces and mix thoroughly to coat. Marinate for at least 30 minutes or up to overnight in the fridge to allow flavors to penetrate deeply and for tenderizing the meat.

2-Second Step: Fry the Chicken
Heat 240 ml (1 cup) sunflower or peanut oil in a large wok or deep skillet over medium-high heat. Once hot, fry the marinated chicken in batches for about 4-5 minutes each, turning occasionally until golden brown and cooked through. Remove and drain the chicken on paper towels, then set aside. This frying step creates a crisp exterior that holds the sauce well and keeps the chicken moist inside.

3-Third Step: Stir-Fry the Aromatics
Reserve about 1 tablespoon of the frying oil in the wok. Add 1 tablespoon sesame oil and heat it over medium heat. Toss in the chopped onion chunks and dried red chilies (10 to 25, depending on heat preference; keep most whole for mild spice). Stir-fry for 2 to 3 minutes until the onion begins to soften and the chilies crisp slightly without burning. This step releases the complex aromas essential for authentic szechuan chicken.

4-Fourth Step: Add Sichuan Peppercorns and Aromatics
Sprinkle 1 to 1 1/2 teaspoons ground Sichuan peppercorns into the wok. Stir-fry for about 1 minute until fragrant and aromatic, allowing the numbing sensation to develop. Then add 3 to 4 cloves of minced garlic, 2 teaspoons minced fresh ginger, and the white parts of 5 scallions. Stir-fry together for 30 seconds until the mixture becomes highly fragrant.

5-Fifth Step: Prepare the Sauce
Stir in 1 tablespoon light soy sauce, 1 tablespoon rice vinegar, 1 tablespoon chili bean paste (or substitute chili sauce), and 1 tablespoon sugar. Mix well and cook for about 1 minute, allowing the sauce to thicken slightly and develop balanced sweet, sour, and spicy notes.

6-Sixth Step: Combine Chicken and Sauce
Add the fried chicken pieces back into the wok. Toss and stir briskly to coat all pieces evenly in the vibrant sauce. Cook for 1 to 2 minutes on high heat, ensuring the chicken becomes hot again and absorbs the aromatic flavors.

7-Seventh Step: Final Touches
Quickly add the green parts of the scallions and toss for a few seconds to incorporate their fresh taste and color contrast. If desired, stir in 1/2 cup toasted cashews or peanuts and sprinkle with toasted sesame seeds for added crunch and presentation.

8-Final Step: Serve
Serve the szechuan chicken immediately while hot over steamed rice or your choice of noodles. This spicy, numbing stir-fry is guaranteed to impress with its bold flavor and satisfying texture. For lighter or vegan adaptations, follow the marinating and cooking steps using tofu or tempeh and adjust oil amounts accordingly.