Soak the peeled split mung beans in warm water for 1 to 2 hours.
Next, water with sugar until the sugar fully dissolves.
Sift and combine the glutinous rice flour, rice flour, and baking powder in a mixing bowl.
Add cooking oil to the flour mixture, then gradually pour in the sugar water. Mix well.
Mix the dough for about 10 minutes or until smooth. Cover the mixing bowl with plastic wrap and allow your dough to rest for 2 to 4 hours.
Drain the mung beans and add them to a saucepan. Cook them with water for 30 minutes over low heat. Cover the saucepan to prevent the water from evaporating, which causes the beans to be burned.
Once the beans have tenderized, add salt, grated coconut (if using), and sugar to the saucepan. Stir well until the mixture is smooth.
Shape the dough into balls (about 1 ounce in weight and 1 inch in diameter). Likewise, shape the filling into balls that are a little smaller than the dough balls. Repeat the above step until you run out of dough and filling. You should be able to make 20 to 24 balls with this recipe.
Coat your hands with a layer of flour so that the dough doesn't stick to them. Flatten the dough ball using your palm and add the filling in the middle. Roll the dough into a ball once again, making sure that the shell wraps around the filling completely and evenly. Repeat these steps for the rest of the ingredients.
Heat cooking oil in a frying pan. Put the sesame balls one by one into the pan. Fry them until golden brown on all sides.
Once cooked, transfer the balls onto a plate lined with paper towels to get rid of the excess oil.
Cook water with some ginger for 5 minutes on low heat, then remove the ginger. Add sugar and stir well. Once the sugar has dissolved, add the roasted sesame seeds and continue to stir until the glaze thickens slightly. Roll these balls over the sugar and sesame glaze to coat.
Enjoy your delicious Vietnamese sesame balls with tea to balance their sweetness.