Prepare the Peaches: Bring a medium pot of water to a boil. Score a small cross on the bottom of each peach. Blanch for 1 minute and transfer to ice water to cool.

Peel and Halve the Peaches: Peel the skins off, halve each peach, and remove the pit. Set aside.

Make the Mochi Dough: In a microwave-safe bowl, mix glutinous rice flour and sugar. Gradually whisk in water until smooth. Cover and microwave on high for 1 minute, stirring twice.

Cool the Mochi: Let the dough cool for 5 to 10 minutes and dust your work surface with cornstarch.

Shape the Mochi: Roll out the dough into a circle about ⅙-inch thick and divide into four equal portions.

Wrap the Peaches: Place a peach half in the center of each dough portion and wrap it carefully, pinching seams to seal.

Final Touches: Place each mochi seam-side down to set for a few minutes before serving.