Cut the chicken into 2 cm cubes, sprinkle with the Cajun seasoning and rub into the raw chicken pieces and set aside for 10-15 minutes. (wash your hands). Heat the oil in a large flameproof casserole or pan over a moderately high heat, add the chicken and fry for about 3-4 minutes, stirring frequently, until the chicken is lightly browned. Add the chorizo and continue to cook for 2 minutes and the chorizo has rendered some of its oil. Remove the chicken and chorizo from the pan with a slotted spoon and set aside. Add the onion and celery to the pan and fry for 2 minutes, add the peppers and continue to fry for 2-3 minutes. Add the crushed garlic and the rice, stir well and fry for another minute. Pour in the stock and stir well. Return the chicken and chorizo to the pan. Bring to the boil, then reduce the heat, cover and simmer for 8 minutes. Add the canned tomatoes and cook for a further 5 ᆞ minutes or until the rice is tender and has absorbed all the liquid and the chicken is cooked through. Season with salt and pepper, take the casserole to the table and serve.