Rinse the sago pearls under cold water until the water runs clear.

In a pot, bring 4 cups of water to a boil. Add the sago pearls and cook for about 30 minutes, stirring occasionally, until translucent.

Once cooked, remove from heat and let sit for 10 minutes. Drain and rinse under cold water to stop the cooking process.

Mix the cooked sago with coconut milk and set aside.

In a mixing bowl, combine the diced mangoes and sugar. Let it sit for 10 minutes to allow the sugar to dissolve and the mangoes to release their juices.

In serving bowls, layer the sago mixture and top with the sweetened mangoes.

Serve chilled or at room temperature.