When the kagami mochi goes on display, it is smooth and looks a little like bread dough before it rises. By January 11, it has lost its youthful freshness and developed serious cracks and crevices. This is good, because it makes the "mirror" so much easier to smash.
In my house, the mound of kagami mochi gets wrapped in a towel and smacked with a meat hammer.
Then what? You'll see in the next post.