Rinse the glutinous rice under cold water until the water runs clear, then soak in a bowl of water for at least 4 hours or overnight.

Drain the rice and place it in a cheesecloth-lined steamer basket. Steam over simmering water for about 25-30 minutes until tender and translucent.

While the rice is steaming, combine coconut milk, sugar, and salt in a saucepan, heating gently until the sugar dissolves.

Transfer the cooked rice to a mixing bowl, pour most of the warm coconut sauce over it, and gently mix. Let it sit covered for about 15 minutes.

Portion the sticky rice mixture into individual cups, layering with slices of ripe mango.

Drizzle with reserved coconut sauce, sprinkle with sesame seeds or mung beans, and garnish with fresh mint leaves before serving.