Wash rice a few times with water, draining each time, until water runs clear.
In large pot, add rice and water. Let soak for minimum 30 minutes or overnight. Do not discard the water.
Add coconut milk, brown sugar, and salt to the pot.
Turn heat to medium high and bring rice to gentle boil. Partially cover with lid and reduce heat so liquid is simmering.
Simmer for 20-25 minutes, or until rice absorbs liquid and is tender. Turn off heat and let rice sit in pot for 5 minutes. Meanwhile, make the coconut sauce.
For the coconut sauce:
In a small saucepan, heat coconut milk and brown sugar until sugar is dissolved.
Remove a few tablespoons of warm coconut milk and whisk in cornstarch to make a slurry.
Pour cornstarch slurry into pot while mixing. Heat until coconut sauce is slightly thickened. If it is too thick, you can add more coconut milk or water.
Decorating:
Cut mangoes using cookie cutters or paring knife.
Scoop sticky rice onto plate. Use clean hands or spoons to shape the rice into your liking.
Add cut mango and melted chocolate on and around the rice as decorations.
Drizzle as much coconut sauce on top as you want.
Top with sesame seeds.
Enjoy!
Notes
Sticky rice can get hard and dry pretty quickly. I recommend storing the sticky rice, separate from the coconut sauce, in an airtight container in the fridge for up to 3 days. The coconut sauce will also keep for about 3 days.To reheat it, cover the rice with a damp paper towel and microwave at 30-second intervals. Top with warmed coconut sauce.