Preheat the oven to 180°C/350°F/Gas 4.
Put the rice in an even layer in the bottom of a large ovenproof dish.
Season the chicken with salt and pepper. Heat 2 tbsp of the oil in a frying pan over a high heat and brown the chicken quickly on all sides, then put it on top of the rice in the ovenproof dish.
Add the remaining oil to the pan and fry the onions and garlic. Once softened, add the peppers and the as many of the chillies as you can bear. Fry for 5 minutes over a medium-low heat until the peppers are soft.
Add the thyme, oregano, smoked paprika, chopped tomatoes and tomato purée/paste. Stir briefly and season with salt and pepper to taste.
Now add the stock and red wine vinegar, bring to the boil, then simmer for 3 minutes. Pour this mixture over the chicken and rice. Cover tightly and transfer to the oven for 45 minutes until the rice and chicken are tender. Sprinkle with coriander leaves and serve warm.