Peel the bananas and slice them into bite-sized pieces. Toss with granulated sugar and let sit for about 15 minutes.

Soak the tapioca pearls and sweet potato pearls in water for about 20 minutes until softened, then rinse well.

Bring a pot of water to a boil. Add the sweet potato pearls and cook until done. Remove and rinse under cold water, then drain.

Add the tapioca pearls to boiling water. When they float to the surface, they're cooked. Remove and drain.

In a pot, combine 1/3 cup coconut milk (about 100 ml) and 1/3 cup water (about 100 ml). Use just enough coconut milk for a rich, fragrant flavor without being too heavy. Add the rock sugar and bring to a boil, stirring until the sugar dissolves. Add the bananas and gently stir. Simmer over low heat for 10-15 minutes until the bananas are soft.

Next, add the cooked tapioca pearls and sweet potato pearls. Stir gently. When both turn completely translucent, they're done. Adjust the sweetness to taste, then add the vanilla extract and turn off the heat.

Ladle the dessert into bowls, sprinkle with roasted peanuts, and enjoy.