Peel the sweet potato, cut into chunks and boil until tender.
While the potatoes are cooking, make the filling. Mix the chopped palm sugar with the granulated sugar and set aside. Then mix the grated coconut with a pinch of salt and set aside.
When the sweet potatoes are cooked, remove and mash them. Add the flour and the green pandan juice and knead into a dough. Shape the dough into marble-size balls, flatten them slightly and put a teaspoon of the sugar filling in the center. Seal and reshape into ball.
Put a pot of water to boil. When it is boiling drop the sweet potato balls in the water and when it cooks, it will float to the top. Remove and drain. Then roll the balls in a dish with grated coconut until it is fully covered. Serve immediately.