If using bone-in pieces, with a sharp knife poke a few holes in the chicken so the marinade can better penetrate. If using boneless, pound any chicken breasts into an even thickness; with the tines of a fork poke holes in the chicken. Pat the chicken dry, then place in a ziptop bag, a large bowl, or a baking dish sized to hold the chicken snugly.
Cut off half of the dark parts of the green onion, finely chop, and set aside for serving (I put them in a small bowl or ziptop baggie in the refrigerator). Chop the remaining white and dark green parts into 1-inch pieces, then place in a mini food processor or high speed blender.
To the food processor, add the garlic, jalapeño, lime juice, oil, brown sugar, thyme, nutmeg, cinnamon, allspice, ginger, salt, and black pepper. Blitz to combine (it’s OK if the mixture isn’t perfectly smooth).
Pour the mixture over the chicken, then turn the chicken to coat it evenly. Cover and marinate in the refrigerator for at least 4 hours or overnight. When ready to cook, let the chicken come to room temperature for at least 15 minutes.
TO GRILL THE CHICKEN. Heat a charcoal or gas grill to medium heat (350°F to 375°F). Clean and oil the grates. Grill the chicken pieces skin-side down (for bone-in) or smooth/presentation side down (for boneless) for 25 to 35 minutes (for bone-in) or 8 to 12 minutes (for boneless), turning halfway through. Chicken is considered done at 165°F. I like to remove chicken from the grill at 155-160°F and allow it to finish cooking while resting. Discard the excess marinade.
TO BAKE THE CHICKEN. Heat your oven to 375°F. Bake the chicken for 25 to 45 minutes (for bone-in—note the time varies a lot depending upon the size of your pieces) or 15 to 25 minutes (for boneless), or until the chicken is cooked through (it should register 155°F on an instant read thermometer; the temperature will rise as it rests). Discard the excess marinade.
Place the chicken on a plate and let rest for at least 5 minutes (resting is mandatory!). Sprinkle with the reserved green onions and enjoy hot.
Notes
TO STORE: Refrigerate leftover Jamaican jerk chicken in an airtight storage container for up to 4 days.
TO REHEAT: Gently rewarm chicken in the oven at 350 degrees F, or heat in the microwave. To keep the chicken moist in the oven, you can cover it with foil in a baking dish and add a splash of broth or water.
TO FREEZE: Freeze leftovers in an airtight, freezer-safe storage container for up to 3 months. Let thaw overnight in the refrigerator before reheating according to the instructions above.