mashed anko (red pean paste
Anko paste is a simple paste of sweetened red beans that appears in a lot of Japanese desserts. There are 3 varieties or stages referring to the texture or basically just how much you squished the beans. Tsubuan refers to whole unmashed bean paste. Tsubushian is a lightly mashed bean paste as in the image above. Koshian is mashed and sieved bean paste with no visible bean chunks.
What you will need
How to cook
A potato masher works great for this, but you can get fine results with a spatula and a little elbow grease. Mash the beans to a rough paste. You will still see some bean husks in there, and that's perfectly acceptable.