Divide the taro paste into 25g portions (16 pieces). Roll them into balls.
Divide the mochi into 10g portions (16 pieces). Roll them into balls. (Don't forget to wear your gloves!)
Wrap each piece of mochi in the taro paste, sealing well. Place in the fridge while working on the dough.
Divide both the white and blue dough into 8 equal portions each.
Wrap one portion of blue dough inside one portion of white dough and seal it tightly. Place the dough on a plate and cover with plastic wrap before working on the next portion. Let the dough rest for 20 minutes, covered with plastic wrap.
Preheat the oven to 160°C (329°F).
Take one dough portion and, using a rolling pin, roll it out into a long strip. Roll it tightly like a Swiss roll. Place it back on the plate and cover with plastic wrap. Repeat with the remaining dough. Let the dough rest for another 20 minutes. It is important to let it rest for the full 20 minutes; otherwise, the blue dough might break through.
Cut the rolled-up dough in half.
With the cut side facing downward, use a rolling pin to flatten each half of the dough gently, then roll it out into a flat disk without tearing the spiral designs.
Place a portion of taro filling in the middle of each rolled-out pastry. Wrap the filling inside the pastry, sealing the ends. Repeat steps 8-10 for the remaining dough, working one at a time to prevent the dough from drying out.
Place the pastries on a baking pan and bake for 25 minutes. Allow the mooncakes to cool on the tray for 5 minutes before transferring to a cooling rack. Serve when completely cooled or chilled in the fridge.