Preheat the oven to 200°C/180°C fan/400°F/Gas mark 6
Cut the sweet potatoes into even-sized wedges and put them in a bowl along with the red onion and 4 of the sprigs of thyme. Add 2 tbsp of olive oil and mix well so that everything is evenly coated. Season with sea salt and black pepper.
Meanwhile, place the chicken in a roasting tin and stuff the cavity with the orange skins, the garlic and the remaining 2 sprigs of thyme. Rub the chicken with olive oil and the smoked paprika. Pour over the orange juice and zest, season with salt and pepper and roast in the oven for 30 minutes.
Add the sweet potato and onion mixture to the roasting tin, tossing well in the juices of the chicken and return to the oven for a further 30 minutes. Next, add the red pepper to the roasting tin, basting well and return to the oven for the final 20 minutes. Remove from the oven and allow to rest for 15- 20 minutes, then serve with the salsa.
To make the salsa, cover the peas with boiling water to defrost and mix together with the chives, the diced avocado, chillies, lime juice and crème fraiche. Season to taste. Refrigerate until ready to serve with the chicken.