Soak the rice in a large bowl of water for 8-9 hours then drain and rinse the rice under running tap water.
Line a steamer with a piece of muslin and add 2-3 blades of screwpine leaves. Spread the rice over and steam for 30-40 minutes. Check and taste the rice after 20 minutes to make sure that the consistency is right. Sprinkle a little water over the rice to help it along. Remove and leave aside to cool.
Heat the coconut milk in a saucepan. Add salt, sugar and corn flour. Remove the saucepan from the heat the moment it starts to thicken.
Serve the glutinous rice with mango slices and a generous serving of sweet coconut cream.