1. Preheat the oven to 350°F (180°C). Heat 1 tbsp of the oil in a large flameproof casserole dish over high heat. Add the chicken thighs and brown, turning once, about 5 minutes. Transfer chicken to a plate and set aside.

2. Pour the remaining 1 tbsp oil to the casserole and reduce the heat to medium. Add the onion and cook about 3 minutes, until softened. Stir in the green and red peppers and garlic and cook for 5 minutes, until they soften. Add the tomatoes, smoked paprika, thyme, oregano, and bay leaf, then stir in the rice. Stir for 1-2 minutes.

3. Crumble in the saffron, then stir in the stock, tomato paste, and lemon juice. Season with salt and pepper.

4. Return the chicken thighs to the casserole, nestling them in the rice. Cover and bake for 15 minutes. Add the peas and bake for 10 minutes more, or until the rice is tender and has completely absorbed the cooking liquid. Serve immediately, while still hot.