Be sure to seal the balls of dough. Otherwise the palm sugar will ooze out when boiled.
Cover the filled Onde Onde with a tea towel to ensure they do not dry up as you are making them. If they did dry and fine cracks appear, moisten with a little water and seal again.
The Onde-Onde balls are cooked once they float to the surface of the boiling water.
You can simmer the Onde-Onde in the boiling water for another 5 minutes to ensure the palm sugar is fully melted inside the dough.
Cooked Onde-Onde can only keep for a day as the grated coconut last for just a day.
To prepare Onde-Onde before hand:
Refrigerate shaped and uncooked Onde-Onde for up to a week or freeze shaped Onde-Onde in freezer bag for up to 6 months. Then when needed, just cook the refrigerated or frozen Onde-Onde in boiling water before coating with fresh grated coconut.