Marinate the diced chicken in soy sauce, rice vinegar, and sesame oil for 10 minutes.
Heat vegetable oil in a large skillet or wok over medium-high heat.
Add the marinated chicken and stir-fry until browned and cooked through, about 5-7 minutes.
Remove the chicken from the skillet and set aside.
Add minced garlic and ginger to the skillet, sautéing for about 30 seconds.
Add the diced bell pepper and cook for 2-3 minutes until slightly tender.
Return the chicken to the skillet along with the green onions and peanuts.
Stir in hoisin sauce and chili paste, mixing well to combine.
Season with salt and pepper to taste, adjusting heat level as desired.
Cook for an additional 2-3 minutes, allowing flavors to meld before serving.