Pick over the rice to remove any dirt or discoloured grains. Wash the rice thoroughly in five or six changes of water, until it runs clear, which signals that all the loose starch has been removed.
Pour 1l/35fl oz/4⅓cups warm water into a large bowl and add 1tablespoon of the salt. Add the rice and leave to soak for no more than 30 minutes, running your fingers through it every so often to help loosen the grains. Strain the rice and rinse under warm water.
Pour 1.25l/44fl oz/5¼cups water into a large saucepan and add the remaining salt. Bring to the boil over a high heat and stir in the well-strained rice, then bring back to the boil and cook, uncovered, for 3 minutes over a high heat, until the grains are soft on the outside but still firm in the centre. Do not stir the rice again, as this could break the grains.
Drain the parboiled rice in a sieve and rinse with tepid water, tossing the rice gently to remove the excess moisture and to separate the grains. At this point you can set the rice aside until you are ready to cook your chosen recipe, if you like. This means that you can parboil the rice the day before you want it, then continue with the recipe the following day. (Once it has cooled, it needs to be stored in the refrigerator, where it can be kept safely for up to 3 days. Return to room temperature before using.)