Rich black sesame mochi with a nutty, chewy filling is a beloved sweet snack. A vegetarian, family treat with bold, fresh sesame flavor.
Lightly toast the black sesame seeds in a dry pan over medium-low heat for 2-3 minutes, stirring constantly until fragrant. Remove from heat and cool.
Finely grind the cooled sesame seeds with sugar and salt in a food processor until they resemble coarse sand.
In a mixing bowl, whisk together sweet rice flour and water until smooth with no lumps.
Add the sesame mixture to the rice flour batter and mix thoroughly. Pour the combined mixture into a lightly greased 8-inch heatproof pan.
Steam the pan over medium-high heat for about 18-20 minutes, or until the surface is set and bouncy when gently pressed. Let cool slightly.
Dust a clean surface with cornstarch. Using a spatula, transfer the mochi onto the surface, sprinkle more starch on top, and let it cool to room temperature.
Cut the mochi into bite-sized pieces, coating each piece well with starch to prevent sticking before serving.