Apparently they are nice sliced, tossed with olive oil, salt and pepper then roasted till caramelised and tender. Never tried them myself. Also known as Jerusalem Artichokes.
Interesting looking things though, enjoy.
Peel them, slice them and cook in olive oil, with a little salt as @mbrownphotography wrote. They are delicious, a little more elastic than a potato and with a slight artichoke aftertaste. a great side for a white meat dish (e.g. a grilled chicken supreme)
Interesting looking things though, enjoy.