First, soak the mung beans for about 30 minutes, then rinse and steam until cooked. Blend the mung beans with the sugar and coconut milk until smooth. Transfer the mixture to a pan and cook over low heat until it thickens and dries out. Let cool, then roll into small balls for the filling.

Divide the dough into 5 portions to make the colors:
1. Green: Blend pandan leaves with a little water, then strain to get pandan juice.
2. Blue: Soak butterfly pea flowers in hot water for about 15 minutes, then strain to get the blue liquid.
3. Red: Puree the red-fleshed dragon fruit and strain to get the juice.
4. Purple: Steam the purple sweet potatoes, mash, and strain for a smooth texture.
5. White: Mix the dough with coconut milk only.

To color the dough: Add a few drops of each natural coloring liquid to a portion of dough and knead until the color is evenly distributed. Repeat for each color. The white dough is already mixed with coconut milk and does not need coloring.

Divide each colored dough portion into small pieces, slightly larger than the filling balls. Flatten each piece, place a mung bean ball in the center, and wrap the dough around it, rolling into a ball. Continue until all the dough and filling are used. If you have leftover dough, roll into small balls and cook them as well. Boil the balls, then transfer to a bowl of cold water and drain.

Next, bring a pot of water to a boil. Drop the dumplings in and cook until they float to the surface. Remove and place in a bowl of cold water.

In a pot, combine the palm sugar, ginger, a pinch of salt, and water. Bring to a boil, stirring until the sugar dissolves. While the syrup is boiling, add the dumplings from the cold water and simmer for about 5 more minutes. For the coconut sauce, heat 1/3 cup coconut milk with a pinch of salt. Mix 1 tablespoon tapioca starch with a little water, add to the coconut milk, stir until thickened, then remove from heat.

To serve: Ladle the dumplings and syrup into bowls, sprinkle with toasted sesame seeds, drizzle with coconut sauce, and add shredded coconut if desired. Enjoy!