Soft red bean mochi with sweet azuki filling is a classic Asian treat. A vegetarian, family-friendly snack with naturally sweet, fresh flavor.
In a medium heatproof bowl, thoroughly combine the sweet rice flour, sugar, and salt. Add water gradually while mixing to ensure no lumps remain.
Cover the bowl loosely with plastic wrap and microwave on HIGH for 2 minutes. Stir the mixture well, scraping down the sides to maintain even texture.
Microwave for another 1 minute, then stir again while checking consistency—mochi should appear slightly translucent and sticky. If opaque spots remain, microwave in 30-second bursts until done.
Generously dust a clean work surface with cornstarch. Pour the steaming hot mochi onto the surface, sprinkle more cornstarch on top, and let cool for 10 minutes.
Divide the mochi into 8 portions using a plastic knife or dough scraper. Flatten each piece, place a heaping spoonful of red bean paste in the center, and gently pinch edges to seal. Roll into smooth balls, re-dusting hands with cornstarch as needed.