Put the chicken and all the marinade ingredients together in a bowl or large roasting bag and toss together. Leave to marinate for 2-3 hours or even overnight in the fridge (covered).
Preheat the oven to 180C (350F).
Remove the chicken from the marinade shaking most of it off. Reserve the marinade.
Heat the oil in a large lidded casserole dish. Pan fry the chicken, skin side down first, over medium-high heat for a couple of minutes until golden. Turn over and cook for two more minutes on the other side and set aside. Wipe the pan clean.
Heat the butter and oil and sweat the shallots for 7 minutes.
Add the rice and peppers and stir to coat in the butter/oil. Add the reserved marinade and stock and bring to a simmer.
Place the chicken over the rice and cover the casserole. Cook for 45-50 minutes or until the rice is cooked.
Serve sprinkled with the chopped spring onions.
Notes
You can use white basmati rice or long grain rice but you might need to cook it for slightly less time.