Heat the oil in a pan and fry the onion until softened. Add the rice and fry for 1 minute. Add the tomatoes, stock, tomato purée, Schwartz for Chef Piri Piri Seasoning, kidney beans and courgette.
Bring to the boil, cover and simmer gently for 15-20 minutes until the liquid has been absorbed and the rice is tender. Stir in the tuna 5 minutes before the end of cooking.