Simmered sweetened adzuki beans.
I've bought Japanese sweet bean cakes whenever I've been able to find them. They're hard to find over here, as westerners usually don't like them.
There is one Japanese food store in Helsinki, but it's downtown, and I rarely go there. Last time I bought a few such cakes, but that got rather expensive too fast. So I thought, can't be all that difficult, can it? And did a search for Japanese sweet beans. And found a recipe:
1 cup azuki beans
10 cups water
1/3 cup sugar
Put 4 cups of water in a pan and add azuki beans. Put the pan on high heat and bring to boil. Stop the heat and drain the water. Put 6 cups of water in a pan and add the boiled azuki beans. Put the pan on low heat and simmer the beans for an hour until soften. Take out excess water from the pan and add sugar. Stir the azuki on low heat for a few minutes until thicken. Stop the heat.
So I bought adzuki beans and got to work.
After an hour of simmering the beans were still hard, so I let them boil for a couple more hours.
Then I removed excess water, added sugar, pounded the lot with my potato masher, and got something bland and not very good. There must be something missing - salt perhaps? A dash of butter? Dunno, I'll try again one of these weeks, cos I still have some adzuki beans.
Dunno if I'll want to make yokan instead - that one uses much more sugar, and agar-agar, while this seems pretty simple.