Let's make some imo youkan!

Take some round-cut and boiled sweet potatoes,

and push them through a strainer.

At the same time, dissolve some agar-agar into boiling water...

Once the agar is all dissolved, add some sugar and bring to a rolling boil.

Then, mix in the strained sweet potatoes.

Put it all into a mold, and after it's cooled down from the cooking, put it into the freezer. After about 2 hours, it'll be done!