Place the rice in a large bowl, cover with water and leave to stand for 4 hours or overnight. Drain well. Set up a steamer or put a rack inside a wok or large, deep pan. Pour in about 5cm/2in water and bring to the boil. Tip the rice into a bowl and place in the steamer or on the rack. Cover the pan tightly, reduce the heat to low and steam gently for 20 minutes. If usin