Put the onion wedges and garlic in a roasting tin. Stir in 1 teaspoon of the paprika and 1 tablespoon of the oil. Place the chicken on top, breast-side face down.
Push the rosemary sprigs into the chicken cavity and place the tin on the lower rack of the halogen oven.
Set the temperature to 200°C (392°F) and roast the chicken for 30 minutes. Transfer the chicken to a plate and add the peppers, chorizo and tomatoes to the roasting tin. Place the chicken on top of the vegetables, breast-side face up. Brush with the remaining oil, sprinkle with the remaining paprika and season with salt and pepper. Cook for a further 25–30 minutes until the chicken is cooked through – check by piercing the thickest area of the thigh with a knife; the juices should run clear. If needed, cook for a little longer.
Leave the chicken to rest in a warm place for 15 minutes before carving. Serve with the vegetables and chorizo, saffron rice and a tomato salad.