Add the suya spice into a bowl and taste for salt with the tip of your tongue. Add more salt if required. Pour the oil in and mix to form a paste.
Rub the paste all over the skin of the chicken, apply under the skin where possible too, to get as much flavour as possible. Leave for at least 30 mins to marinate.
Heat the oven to 200°C or 180°C fan.
Peel the yam and cut into batons. Keep in a bowl of water to prevent browning.
Peel the onions and cut into quarters. Wash the carrots and remove the top. Cut the broccoli into smaller pieces.
Pour the yam and vegetables into the bowl containing the suya spice paste. Toss well.
Add the chicken skin side up on the tray. Arrange the yam, carrots, and broccoli around the chicken thighs and place the tray in the oven.
Allow to cook for 30 - 40 mins. Check the chicken is cooked through before removing from the oven.