Start brown or white rice and 10 minutes before it is done begin your stir fry.
Heat a tablespoon of vegetable oil over high heat in a large skillet. Add chicken and stir fry for 2-3 minutes, add bell peppers and stir fry 2 minutes more. Remove chicken and peppers to a plate and add 2 tablespoons more oil to the pan. Add ginger and garlic and stir fry 15 seconds then add in peanut butter, soy, stock, chili paste and sesame oil and stir to combine into sauce. Add chestnuts and scallions and toss 1 minute, add chicken and peppers back to pan with peanuts and turn to coat in sauce. Serve over rice.