Fill a roomy saucepan with water, bring to the boil and tip in a heaped teaspoon of salt - the water will bubble furiously. Add turmeric and the cinnamon stick to the water. Pour in the rice, stir once and return to the boil, then turn the heat down a little so that the water is boiling steadily, but not vigorously. Boil uncovered, without stirring (this makes for sticky rice) for 10 minutes. Lift some out with a slotted spoon and nibble a grain or two. If they're too crunchy, cook for another minute and taste again. They should be tender but with a little bite. Drain the rice into a large sieve and rinse by pouring over a kettle of very hot water