How to make anko (あんこの作り方はここで)
http://www.youtube.com/watch?v=gXxAL5cR3cQ&feature=channel_video_title
Other than anko, all you need is glutinous rice(Mochi kome) or you can also add normal rice (10%-20% of glutinous rice). You may want to mash the rice a little when it's cooked. It's up to you.
Don't forget to have green tea :)
もち米に対して20%位の割合の普通の米。炊き上がったらお好みで軽くつぶします。緑茶も忘れずに。