1.Heat the grill of a covered barbecue over a high heat. Meanwhile, combine spices, powders and salt in a plastic bag. Place the chicken in the bag, a few pieces at a time; shake to coat evenly.
2.Drizzle the chicken with oil; cook on barbecue grill for about 6 minutes, turning until all sides have char marks and are starting to crisp.
3.Place all the chicken on one half of the barbecue and turn off the burners underneath the chicken. Leave the burners on the other half at a medium-high heat, so there is no direct heat under the chicken. Lower the hood on the barbecue; cook for about 25 minutes. Check that chicken is cooked by piercing the thickest part of the biggest piece with a skewer. If juices run clear, it will be cooked through. If not, lower the hood and check at 5-minute intervals. Time will depend on the size of the chicken pieces and heat of the barbecue.
4.Serve chicken with a green salad, steamed rice and a piri piri sauce, if desired.