Heat the oven to 2000C or 1800C fan.
Mix half of the suya spice with butter or oil, add a little salt; then rub all over the skin of the chicken. Rub under the skin where possible too.
Toss the vegetables in oil, with a sprinkle of the spices. Keep the tomatoes and peppers separate from the potatoes and onions.
Place the chicken on the pan, then arrange the potatoes and onions around the pieces.
Allow the to cook for 30 mins.
Bring out of the oven, turn the potatoes over and sprinkle some more spice mix over the chicken.
Add the tomatoes and the green peppers.
Place the tray back in the oven
Allow to cook for further 10 mins. Check that the chicken is cooked through before removing from the oven.