Heat the oven to 150c/fan 130c/gas 2. lightly butter a 1.5 litre ovenproof dish. Toss the rice, cardamom pods and sugar into the dish. Stir in the milk, dot with butter and put in the oven.
Cook for 30 minutes then stir the rice and return to the oven for a further 30 minutes before stirring again. Return to the oven for a final hour without stirring. By this time the rice should be tender and creamy. Serve the rice pudding hot with jam or lightly poached apples.