After 1 ½ hour of chilling your ice cream balls you can begin making your mochi dough. Place the glutinous rice flour and sugar in a mixing bowl. Stir to combine well.
Add in the water and whisk until smooth. If using, add a few drops of food coloring and mix in.
Cover the mixing bowl loosely with plastic wrap and microwave for 1 minute (I am using a 1460 Watt microwave, times may vary depending on the power of your microwave)
Remove bowl and using a rubber spatula dipped in water (to prevent sticking) mix the ingredients. There will be some solids and still some liquid, just give it all a good mix.
Cover with plastic wrap again and microwave for 30 seconds followed by another good mixing to bring the dough together into a ball with a wet rubber spatula spoon. Repeat with one more round of 30 seconds in the microwave and stirring.
Place a large piece of parchment paper on the counter top and dust generously with cornstarch or potato starch.
Pour mochi dough onto the parchment paper, dust the mochi with cornstarch and roll out until it is a little more than ¼ inch thick.
Use a cookie/biscuit cutter about 3” diameter to cut out circles. Dust off excess cornstarch/potato starch with a dry pastry brush.
Place each circle on an individual piece of plastic wrap. The size of the plastic wrap should be at least 7 inches by 7 inches or bigger. Stack the mochi dough with plastic wrap on top of each other and place on a small plate. Chill in the fridge for 30 minutes or the freezer for 10 minutes.