In a medium-sized heatproof bowl, combine rice flours and sugar. Stir to incorporate.
Slowly stir in the hot water.
When the mixture is too stiff to be mixed with a spoon, use your hands to knead in the water.
Wrap the dough loosely with plastic wrap and microwave for 3 minutes.
Use a pestle dampened with water to knead the dough. After the dough has cooled enough to handle ~3-5 minutes. The dough will become translucent and bouncy in texture.
If you don't have a microwave, tear the dough into 2" pieces. Place into a steamer basket and steam for 20-25 minutes.
Use dampened hands to further knead the dough until it has the texture of an earlobe.
Divide the dough into 3 equal portions. Cover loosely with plastic wrap to prevent drying.
Add 1-2 drops of red food coloring to one portion. Knead until the color is uniform. Set aside.
Add 1-2 drops of green food coloring to another portion of dough. Knead until the color is uniform.
Roll the dough into a 1 1/2" diameter snake. Cut into 1 1/2" piece and roll into balls.
Dampen a bamboo skewer with water. Skewer the dango beginning with the green, followed by white, and pink.