Step 1: Prepare the Watermelon

• Cut the watermelon in half and scoop out the flesh, removing any seeds.

• Blend the watermelon flesh until smooth.

• Measure out 300 g of watermelon juice and set aside.

Step 2: Make the Mochi Dough

• In a large bowl, combine the glutinous rice flour, cornstarch, and sugar.

• Gradually add the watermelon juice while stirring continuously until fully combined and smooth.

• For best results, sift the mixture to remove any lumps.

Step 3: Microwave the Dough

• Cover the bowl with plastic wrap and poke a few small holes to release steam.

• Microwave on high for 5 minutes, until the mixture becomes thick and translucent.

Step 4: Add Butter and Knead

• While the dough is still hot, stir in the butter until completely melted and incorporated.

• Let the dough cool slightly, then knead for about 5 minutes until smooth and elastic.

Step 5: Chill

• Transfer the dough to a parchment-lined container and flatten the surface evenly.

• Refrigerate for at least 3 hours to allow the mochi to fully set.

Step 6: Shape

• Dust your work surface with cooked glutinous rice flour to prevent sticking.

• Remove the chilled dough, cut it into strips, then slice into bite-sized pieces.

• Dust lightly with more cooked flour if needed.