The block design is actually a "folded" Flying Geese block. I found an excellent tutorial online (Ricky Timms & Alex Anderson video) and another tut that shows how to turn down and top-stitch the edges to create a curved-triangle shape (curved goose sounds too weird!). I had to play around with it quite a bit to get the look I wanted.
I've completed my blocks but will add sashing to make an 18" pillow cover. Check back here soon for further details. I will be posting links and hints on this technique.