The "Acorn" is acorn squash, of course! ;) Further adventures in trying to feed my liquid-tarian 13-month-old son. When I was making it, I had some fresh grated ginger lying around from another recipe and the smell seemed to be calling me to put it into the smoothie. Turned out to be a great combination. I didn't include cooling time for the squash. If you don't want to cool it, you could probably just add some crushed ice and blend.