1. In a bowl combine sweet rice flour, sugar and salt, stir everything.
2. Gradually add the water and stir until all ingredients are blended well.
3. Cover with plastic wrap, cook in microwave for 3 minutes.
4. Remove the plastic wrap and check if the dough is cooked, stir for 3 minutes.
5. Divide the red bean paste into 8 equal size balls.
6. Sprinkle some cornstarch on a work top, transfer the dough on the worktop and roll it into a 16 inch log.
7. Cut into 8 two inch pieces.
8. Flatten each piece and stuff it with red bean paste and seal the edges, roll it smooth and cover it with corn starch.
9. Serve the sweet rice cake with red bean paste as a snack.