In a medium microwave-safe bowl, combine the glutinous rice flour and sugar. Gradually whisk in the water until the mixture is smooth and free of lumps.

Cover the bowl with a wet paper towel or a microwave-safe plate. Microwave the mixture on high for 1 minute, stir, then microwave for an additional 2 minutes.

Allow the banana mochi dough to cool for about 5 to 10 minutes in the bowl.

Dust your work surface with cornstarch and transfer the cooled dough onto it. Shape the dough into a rectangle or divide it.

Using a sharp knife, cut the banana mochi into eight equal pieces, dusting each with cornstarch.

Flatten each square of mochi dough, place a chunk of banana in the center, fold the edges over the banana, and pinch to seal.

Place filled mochi pieces seam-side down on a plate and chill in the refrigerator for at least 1 hour.

Serve and enjoy your homemade Banana Mochi, optionally with vanilla ice cream or fresh fruit.