Rinse the sago pearls under cold water until the water runs clear.
Boil 1 cup of water in a pot.
Add the rinsed sago pearls to the boiling water and stir continuously for about 10-15 minutes until translucent.
Drain the sago and rinse under cold water to stop the cooking process.
In a separate pot, heat the coconut milk and sugar over medium heat until the sugar dissolves.
Add the cooked sago to the coconut milk mixture and mix well.
Remove from heat and let it cool to room temperature.
Serve the mixture in bowls, topped with diced mango and garnish with mint leaves.