In a bowl add soy sauce, rice vinegar, cornflour, sesame oil, honey, salt, and black pepper in a bowl to make the marinade. Mix in the chicken pieces until coated well. Cover the bowl and refrigerate for at least 30 minutes.

In a separate bowl, make the sauce by mixing together soy sauce, hoisin sauce, rice vinegar, honey, sesame oil, and red chilli flakes. Set aside.

Heat vegetable oil in a large frying pan or wok over medium-high heat. Add diced onions and bell peppers and stir-fry for 2-3 minutes until they soften.

Add minced garlic and dried red chillies to the pan and stir-fry for 1-2 minutes until fragrant.

Add the marinated chicken to the pan and stir-fry for 5-7 minutes or until no longer pink. Season with salt and black pepper to taste.

Pour the sauce into the pan, along with unsalted peanuts. Stir-fry everything for another 1-2 minutes until the sauce thickens and coats the chicken and vegetables evenly.

Finally, garnish the dish with chopped spring onions and serve hot with rice or noodles. Enjoy your homemade kung pao chicken!