In a mixing bowl, combine glutinous rice flour, water, and sugar. Whisk until smooth.
Cover the bowl with plastic wrap and microwave for 2 minutes. Stir the mixture, then microwave for another 1-2 minutes until the dough becomes translucent.
Dust a clean surface with cornstarch. Transfer the mochi dough onto the surface and let it cool slightly.
Divide the dough into 8 equal pieces. Flatten each piece and place a small amount of boba pearls and whipped cream in the center. Pinch the edges to seal and shape into balls.
Dust the finished mochi with more cornstarch to prevent sticking. Enjoy!