Cut the sweet potato down the middle lengthways, then slice into 2cm thick slices and place on roasting tray.
Add the onion and the chicken legs.
Break up the garlic and add it unpeeled to the tray, removing only the excess outer skin.
Add the ginger, olive oil, salt and pepper and scrunch everything together so everything is coated in olive oil.
Turn everything once after 15 minutes to ensure even cooking and put back into the oven for another 20-25 minutes until the skin is a nice golden colour and the flesh starts to come away from the bone.
Turn everything around in the oil once more and divide between four plates.