Rinse 1 cup of sticky rice under cold water until the water runs clear. Soak in water for at least 1 hour or ideally overnight.

After soaking, drain the rice. Transfer to a heatproof bowl lined with cheesecloth and prepare your steamer.

Once water is boiling, place the bowl of rice in the steamer, cover tightly, and steam for 20-25 minutes until translucent and sticky.

Combine 1 cup coconut milk, 1/4 cup sugar, and a pinch of salt in a saucepan over low heat until sugar dissolves, about 5 minutes. Do not boil.

To thicken the sauce, mix 1 tablespoon cornstarch with water to create a slurry and stir into the warm mixture for about a minute.

Once the rice is done steaming, transfer to a bowl and pour about 1 cup of coconut sauce over the rice, folding it in gently.

Serve by scooping sticky rice onto a plate, adding mango slices, drizzle additional coconut sauce, and garnish with sesame seeds or peanuts if desired.