Unborn

Referred by Alan Watts.
Bankei is an important chester in Zen history and his style is very unique.
Unborn mind, buddha mind it is.

The book has three sections: (1) Bankei's sermons. This is where you really learn about unborn mind. However it gets s little repetitive because Bankei uses the same way and metaphors to explain it.
(2) The Dialogues and (3) Unnecessary Words: I liked these a lot because most of them are like little stories.