Wash the glutinous rice thoroughly under cold running water until the water runs clear. This usually takes 5-7 rinses.

Place the washed rice in a large bowl and cover with fresh cold water. Let it soak for at least 2 hours, or ideally overnight (4-8 hours). Soaking ensures even cooking and a tender texture.

Drain the soaked rice well using a fine-mesh sieve. Transfer the drained rice to a steamer basket lined with a clean cheesecloth or a banana leaf (if available).

Bring water to a boil in the bottom pot of your steamer. Place the steamer basket over the boiling water, ensuring the water does not touch the rice. Cover tightly and steam for 20-25 minutes, or until the rice is tender, translucent, and sticky. Flip the rice halfway through steaming for even cooking.

While the rice is steaming, prepare the coconut sauce. In a medium saucepan, combine the full-fat coconut milk, granulated sugar, and salt. Heat over medium-low heat, stirring constantly with a whisk until the sugar and salt are fully dissolved. Do not boil the sauce; just bring it to a gentle simmer.

Remove the sauce from heat immediately once the sugar and salt are dissolved. This ensures the sauce remains creamy and does not curdle.

Once the rice is cooked, transfer it immediately to a clean mixing bowl. Pour about 3/4 of the warm coconut sauce over the hot sticky rice. Stir gently with a spoon or spatula until the rice has absorbed most of the sauce and becomes glossy.

Cover the bowl with a lid or plastic wrap and let it sit for at least 15-20 minutes. This allows the rice to fully absorb the sauce and become even more tender and flavorful.

While the rice is resting, peel and slice your ripe mangoes. For presentation, you can slice them into attractive fan shapes or simple strips.

To serve, scoop a portion of the warm sticky rice onto a plate. Arrange sliced mangoes alongside the rice. Drizzle generously with the remaining coconut sauce. Garnish with toasted sesame seeds, if desired. Serve immediately and enjoy!