Make the Sweet Coconut Sauce: Add water and palm sugar to a saucepan. Stir over medium heat until the sugar dissolves and the mixture thickens slightly. Optionally add pandan leaves for aroma. When the syrup is sticky and boiling, add shredded coconut topping if available, stir again until boiling, then turn off heat and set aside.
Prepare the Dough: Sift the glutinous rice flour into a mixing bowl. Gradually add warm water a little at a time, mixing with a wooden spoon or your hands. Knead the dough until it becomes glossy, smooth, and no longer sticks to your hands or bowl. Wrap the dough in plastic wrap and let it rest for about 10 minutes.
Shape the Dumplings: Take a small portion of the rested dough about bite-sized. Roll it into a ball in your palm, then gently press it into a small patty or flat shape as preferred.
Cook the Dumplings: Bring a pot of water to a rolling boil. Add the shaped rice patties/dumplings to the boiling water. Boil for about 3 to 5 minutes or until the dumplings float to the surface.
Cool the Dumplings: Once the dumplings float, scoop them out and soak them in cold water for about 30 seconds to stop cooking and firm up the texture.
Combine Dumplings with Coconut Sauce: Turn the heat on low under the sweet coconut sauce. Add the cooked dumplings into the sauce and gently stir to coat them evenly. Heat through briefly and then serve.