Rinse 1 cup of glutinous rice under cold water until the water runs clear. Soak the rice in water for at least 4 hours or overnight. Drain the rice and place in a steamer lined with cheesecloth. Steam for 20-30 minutes until soft and translucent.

In a medium saucepan, combine 1 cup of coconut milk, ½ cup of white sugar, ¼ teaspoon of salt, and optional pandan leaves. Heat over medium heat, stirring gently for about 3 minutes until the sugar dissolves completely.

Carefully transfer the steamed glutinous rice to a mixing bowl. Pour half of the warm coconut sauce over the rice, mixing gently. Cover and let it soak for 20 minutes.

In a small pot, mix ½ cup of coconut milk, ¼ teaspoon of salt, and 2 tablespoons of rice flour. Cook over low heat, stirring continuously for about 5 minutes until thickened.

To serve, scoop sticky rice onto a plate, arrange fresh mango slices beside it, and drizzle the thickened salted coconut sauce over both.