Begin by bringing 4 cups of water to a rolling boil in a medium saucepan. Add 1 cup of sago pearls and cook them for about 15 minutes.

Once they turn translucent, remove from heat and cover, letting them sit for an additional 15 minutes to ensure they're perfectly chewy.

After the sago pearls have finished cooking, carefully strain them in a fine-mesh sieve and rinse under cold running water to prevent sticking.

In a blender, combine 2 cups of diced ripe mango with 1 cup of chilled evaporated milk and blend until smooth.

In a large mixing bowl, gently fold together the cooked sago, 1 cup of remaining diced mango, and any optional jellies. Pour in the blended mango mixture along with 1/2 cup of coconut milk.

Stir everything until combined, tasting to adjust sweetness with additional condensed milk if needed.

Cover the mixing bowl and refrigerate for at least 1 hour to allow the flavors to meld.

Serve the chilled dessert in individual cups over ice, garnished with fresh fruit if desired.