Rinse the rice under cold water until the water runs clear.
Add the rice to a large pan, and pour over the water.
Place a lid on the pan, and let it simmer on a low heat until the water is absorbed.
Pour over the milk,, reserving half of a cup for later on, then give it a good stir, and let it simmer again for 15 minutes.
Add the sugar, mix well, then add the cinnamon and cardamom.
In a small ramekin, mix the cornflour with the reserved milk to get a smooth mixture.
Pour it over the rice, and use a spatula or a wooden spoon to mix well until the thickens.
Transfer the mixture to an ovenproof fish or several smaller dishes - I used 2 clay pots.
Preheat the oven to 200 degrees Celsius (390 Fahrenheit).
Place the pots in a deep baking tray, half fill the tray with hot water, and bake the pudding for 30 minutes or until it forms a golden brown crust.
Remove from the oven and leave to cool.