Rinse 1 cup of sticky rice in cold water until clear, then soak in cold water for at least 1 hour.

Drain rice and steam in a basket lined with cheesecloth over boiling water for 20-25 minutes until translucent.

In a saucepan, combine 1 can of coconut milk, 1/4 cup sugar, and 1/2 teaspoon salt. Heat over medium-low, stirring until dissolved (about 5 minutes).

Transfer steamed rice to a mixing bowl and pour 1 cup of the coconut sauce over it, mixing gently to combine.

Scoop sticky rice into serving bowls, add sliced fresh mango, drizzle with remaining coconut sauce, and top with toasted sesame seeds if desired.