Mix the glutinous rice,sugar and water in a mixing bowl.
Mix by hand until you are able to easily make a dough. If the mixture is too wet, add glutinous flour 1 teaspoon at a time until you can form a ball .
When the mixture is ready to work on, divide into 2 put in a separate bowl.
Color each bowl mixture with purple and the other bowl mixture with orange food color.
Form mixture into small balls and set aside.
Pour water in a large pot and add sugar, yam and sweet potato. Let boil in medium heat to soften yam and sweet potato.
When it's boiling, add in the coconut milk and the glutinous rice balls. Let simmer and let the glutinous balls float on top and test one piece and check if it is cook through inside. When there is a hint of solid white inside the balls, continue cooking in low heat and check again.
When ready, add the langka and the cooked tapioca pearls and let simmer in low fire for another 3 minutes. Turn off fire.
Serve it hot!