Boil the rice in plenty of water until just done, about 9 minutes. Drain in a colander and rinse briefly to stop the cooking process. Place the rice in a large mixing bowl and add the spring onions and season with salt and white pepper. Spread the rice out on a serving platter.
Slice the mushrooms and fry in 2 or 3 batches in a large frying pan until cooked, about 5 minutes each time. When all the mushrooms are cooked add them all to the pan and pour in the oyster sauce. Fry for a further 2 minutes, stirring to mix. Set aside.
Using a serving spoon, make deep diagonal furrows in the rice. Nestle spoonfuls of the oyster mushroom mix into the furrows so that you have loose “stripes” of mushrooms in the rice.
Sprinkle with the snipped chives.