Pour boiling water over the aburaage to remove excess oil. Cut both pieces in half and use a rolling pin or hit with the back of a knife to soften them (this will make them easier to open).Cut the mochi blocks in half.
Slowly pull apart the two faces of each piece of aburaage, taking care not to break them.
Put a mochi cube inside an aburaage pouch, then fold the top closed in a zigzag pattern, like a fan. Thread a toothpick through the folds to hold the pack closed. Repeat for the other 3 pieces.
Put the broth ingredients into a pot, add the tofu pouches and bring to a boil. Reduce heat to low, cover with a drop lid and simmer for 20 minutes.