Start by mixing your chicken pieces with soy sauce and cornstarch in a bowl. This step not only tenderizes the chicken but also boosts its flavor. Leave it to marinate for 10-15 minutes as you get the other ingredients ready.
Combine hoisin sauce, soy sauce, rice vinegar, sugar, sesame oil, and a cornstarch slurry in a bowl. Stir everything together until the sauce is smooth and well blended. Once ready, set it aside for later use.
Add a tablespoon of vegetable oil to a wok or skillet and heat it over medium-high heat. Toss in dried red chilies and stir for 20-30 seconds until they release a fragrant, smoky aroma. Be careful not to burn the chilies!
Add the marinated chicken to the hot wok. Stir-fry it for about 3-4 minutes until the chicken is fully cooked and golden. Once done, remove it from the wok and set it aside.
Pour another tablespoon of oil into the wok. Add ginger and garlic, stirring until fragrant. Next, toss in bell peppers and zucchini. Stir-fry them for 2-3 minutes, keeping the vegetables crisp and colorful.
Return the cooked chicken to the wok, then pour in the prepared sauce. Stir well to coat every piece evenly. Add roasted peanuts and the white parts of the green onions to enhance the texture and flavor. Cook for another 1-2 minutes.
Remove the wok from the heat and garnish the Kung Pao Chicken with the green parts of the onions. Serve immediately with steamed rice or noodles for a delicious dish!