Boil the water and add the sago pearls. Boil for 10 minutes, stirring continuously to separate the sago and prevent them from settling at the bottom of the pot.
Turn off fire and cover pot. Set aside for 10 minutes. Drain sago, rinse in running water and set aside.
Bring the palm sugar and water to a boil, stirring to dissolve the sugar. Add the durian flesh and stir with a wire whisk until sauce is smooth - the durian fibres will get caught in the whisk and you can remove them easily.
Add banana, coconut milk and salt. Stir over a medium flame until the mixture comes to a boil. Add cooked sago pearls, stir and remove from heat. Serve warm.