Scoop about ⅓ cup of chocolate ice cream into each paper cup. Prepare six scoops in total.

Freeze the scoops for thirty minutes.

In a bowl, combine glutinous rice flour, cocoa powder, and powdered sugar. Mix well.

Gradually add water, stirring until smooth.

Wrap the steamer lid with a cloth to prevent condensation from dripping.

Steam the mochi mixture for fifteen minutes.

Spread cornstarch over a tray.

Transfer the cooked mochi onto the tray and dust the top with more cornstarch.

Dust a rolling pin with cornstarch and roll out the mochi dough to about 2-4 mm thick.

Cut the dough into six squares, each about 15 cm x 15 cm.

Remove the ice cream from the paper cups and place each scoop onto a dough square.

Gather the dough edges around the ice cream, pinching at the base to seal.

Trim any excess dough and wrap each mochi ball tightly with cling wrap.

Freeze the wrapped mochi balls until firm.

Serve straight from the freezer when ready.