Prepare the Jerk Marinade: In a food processor or blender, combine the Scotch bonnet peppers, onion, garlic, ginger, green onions, soy sauce, olive oil, lime juice, brown sugar, thyme, allspice, cinnamon, nutmeg, cayenne pepper, black pepper, salt, and optional dark rum. Blend until smooth. Be cautious when handling Scotch bonnet peppers; wear gloves and avoid touching your face.
Marinate the Chicken: Place the chicken pieces in a large bowl or a resealable plastic bag. Pour the jerk marinade over the chicken, ensuring each piece is well coated. Massage the marinade into the chicken. Cover the bowl or seal the bag and refrigerate for at least 4 hours, or preferably overnight, to allow the flavors to penetrate deeply.
Preheat Your Grill: Preheat your charcoal or gas grill to medium-high heat (around 400-450°F or 200-230°C). If using a charcoal grill, you can arrange the coals to create a slightly cooler zone for indirect cooking if needed.
Grill the Chicken: Remove the chicken from the marinade, letting any excess drip off. Discard the remaining marinade. Place the chicken pieces directly on the preheated grill grates. Grill for about 20-25 minutes, turning every 5-7 minutes, until the chicken is cooked through and has a nice char. The internal temperature should reach 165°F (74°C).
Rest and Serve: Once cooked, remove the chicken from the grill and let it rest for 5-10 minutes before serving. This allows the juices to redistribute, ensuring the chicken is extra moist.