In a bowl, mix the glutinous rice flour, rice flour, sugar, salt, and vanilla powder. Gradually add the warm water while stirring until combined. When the dough feels just right—not too dry—add the mashed sweet potato and mix until smooth. Let the dough rest for 30 minutes.

Soak the split mung beans in water until soft, then cook until done. Mash the beans, then cook them in a pan over low heat to dry them out. Add sugar, coconut, and a little vegetable oil, mixing well. When the mixture is ready, add a few drops of orange extract for fragrance. Let the filling cool, then roll into small balls.

To assemble, pinch off pieces of dough and flatten them. Place a mung bean ball in the center, then wrap the dough around and roll into a ball. Roll each ball in sesame seeds, then roll again to help the seeds stick. Heat enough oil in a pan for deep frying. When the oil is hot but not smoking, gently add the balls. Fry over medium heat until golden brown. Remove and drain on paper towels.