Rinse, dry, and hull the strawberries.
Wet your hands and make 6 small aduki bean balls weighing around 30g each (using plastic gloves may be easier). Put aduki bean balls in the fridge for 15 minutes.
Put each aduki bean ball on a sheet of cling film and flatten them out. Wrap the strawberries with the aduki bean balls by molding all the way around each strawberry.
In a medium microwave-safe glass bowl, mix shiratamako and sugar with a whisk.
Using a whisk, slowly add water in while stirring. Stir until the mixture has reached a thick consistency. Cover loosely with cling film.
First, microwave 1 minute. Mix well with a wet silicone spatula. The mixture is still whitish and floury.
For the second time, microwave 1 minute again, and mix well with the wet silicone spatula. Now it starts to resemble mochi, but there are still some floury parts.
For the last time, microwave only 30 seconds. Now the mochi mixture should look translucent. (Heating time would vary depending on the microwave but make sure the whole mochi is translucent)
Sift corn starch on the tray and put the mochi on top.
With silicone spatula or kitchen scraper, fold the mochi in half one time so it won’t be as sticky and then divide into 6 equal pieces.
Put some corn starch on your hands, then flatten and expand each mochi into a 3” circle. Then put the put the aduki bean paste covered strawberry on top of it, with the tip facing down.
Start covering the strawberry from all sides and use your thumb to hold the mochi on top.
When all sides of mochi meet at the top, twist and close. Hold the mochi with both hands and form into nice round shape. Repeat the process for the remaining mochi.
Serve at room temperature and they must be consumed within 2 days.