Put the adzuki beans in a pressure cooker with plenty of water.
Cook under pressure for 30 minutes, then leave to cool down naturally. Wait until the sides of the cooker are cool enough to touch.
If there is any water left in the pot, drain it off. You don't have to completely drain.
Add sugar and cook over low heat. Mix continuously with a wooden spatula so the beans don't burn on the bottom.
When you add sugar, it should get quite watery. This is how it looks right after sugar is added.
In about 5 minutes, it becomes quite syrupy. It's not stiff yet, but when the anko cools down, it hardens so you can stop cooking at this point.
Use for ohagi (a type of Japanese wagashi with mochi rice covered in anko).
Use as a filling in mochi dumplings.
This is a bonus photo.
Story Behind this Recipe
I was busy and didn't have a lot of time.
After the beans have been cooked, make sure to drain them off. The mixture burns easily after the sugar is added, so keep stirring. Even if the bean paste is still soft, it will firm up when it has cooled down. It also becomes less sweet-tasting when it's cold, so I recommend making it pretty sweet.