Make jerk marinade by placing the ingredients In a blender or food processor and process into a wet paste.
Place cut up chicken in the ziplock bag or large bowl, add the salt, all purpose seasoning and 2 tbsp of jerk marinade all over. If using ziplock bag, seal it and massage the seasonings and marinade into the chicken making sure get into every crevice as much as you can. If using your hands, massage salt, seasonings and marinade into as much of the chicken as possible making sure to get under the skin and every crevice and corner.
Cover bowl or place ziplock bag on a tray/plate and marinate in fridge for at least 6 hours but preferably overnight (12-24 hrs).
When ready to cook, remove chicken in jerk marinade from fridge for at least 30 minutes.
Preheat oven to 400℉ /200℃
Place chicken on a wire rack inside a baking tray OR on a foil lined baking tray greased with cooking spray. Be sure to give each piece enough space.
Place baking tray on the middle rack in oven and bake for 40-45 minutes turning chicken on the other side at the halfway mark.
Make gravy while chicken is in it's last 15 mins of cooking. Place 1/2 tbsp wet jerk seasoning (or leftover from chicken bowl) plus 1/2 cup water in a small pan and bring to a boil. Lower heat and slowly whisk in ketchup, 1 tsp brown sugar and cornstarch slurry until mixture starts to thicken. Taste and adjust for salt to your liking.
During the last 5-7 minutes of cooking time mins, brush sauce over chicken using a pastry brush.
Optional: Turn oven to broil during the last 3 minutes to get that charred skin.
Chicken is cooked when inserting a meat thermometer reads 165℉ and the chicken is a deep brown color.
Remove and let sit for 5 minutes then serve with rice & peas.