ooh I made one just the other day - there are lots of different recipes about, most call for at least 2 hours cooking. I used the Delia Smith recipe with a slight variation - you need 40z (110g) pudding rice, 1 and a half pints of milk (845 ml), 2oz butter (50g), 3oz caster sugar (75g, fresh nutmeg (she says to use 3 eggs (but I didn't)
preheat oven to Gas Mark 2, 300F (150C)
Put rice into a saucepan and the milk and bring it slowly to simmering point, then cook it very gently until the rice is practically tender which should take about 10 mins. Then add the sugar and the butter and stir until dissolved, pour the mixture into a 2pt (1 litre) baking dish sprinkle on some freshly grated nutmeg and bake for 40 mins or longer if you prefer a thicker consistency
I cooked mine for 40 mins then turned off oven while I ate my tea then dished up rice pudding and it was lovely, stodgy and there was no liquid, but that is personal preference