hoisin sauce • oyster sauce • mirin (sweet rice wine) • brown sugar • soy sauce • crushed red pepper flakes (or more) • boneless skinless chicken thighs or breasts, cut into 1-inch thick strips or cubes • garlic (3 if small cloves) • red bell pepper, sliced • yellow onion, sliced • green onions, chopped diagonally • peanut oil (or vegetable or canola oil) •