Prepare mochi filling by rolling about 1-2 Tablespoons of the mochi filling of choice into balls. Set aside.
Sprinkle the starch onto a clean dish or baking pan. Set aside.
In a microwaveable glass bowl (like Pyrex), mix the mashed purple sweet potato and sweet rice flour. Use your hands to try and incorporate the purple sweet potato into the flour the best you can.
Add in water and stir mixture using a spoon.
Microwave the mixture for 60 seconds.
Use a SOLID METAL spoon (wooden spoons might break!) to stir the cooked mochi so that the cooked and uncooked parts are evenly mixed.
Microwave the mochi mixture again, for another 60 seconds. Stir until the dough is slightly glossy and translucent.
Pour the cooked mochi onto the baking pan sprinkled with starch.
Cut the mochi into 6 pieces using scissors or a dough cutter.
Eat as is, or fill with prepared filling. Enjoy!
