This root vegetable, which closely resembles a knob of ginger, was once commonly known as the Jerusalem artichoke, but the name was deemed too confusing since it neither hails from Jerusalem nor is it an artichoke. There are many explanations for the name, but one possibility is that something got lost in translation from the original Italian, "girasole articiocco."
To eliminate such confusion, it is now marketed more often as the sunchoke, although one may still see "farmers" at farmers markets stubbornly clinging to the old nomenclature — which only goes to show that giving something a second name usually just makes things a bit more confusing, but we won't dwell on that.
The sunchoke plant is actually a type of sunflower originally grown by Native Americans in the late 16th century and brought back to Europe by Samuel de Champlain not long after. In France, the plant was transformed into a commercially viable crop. It is the edible root of this plant that is harvested and now sold in markets.
When raw, a sunchoke has a crunch and juiciness comparable to that of a water chestnut, but it has a sweeter, earthier flavor that makes it a good alternative to potatoes when cooked, a boon for diabetics. It is easily puréed, roasted, and even fried into chips.
Sunchokes pair well with seafood as well as chicken and can be tossed into soups, stews, salads, and even risotto. There's no need to peel them, but it is a good idea to give them a nice scrub before eating, and if using them raw, slicing them thinly works pretty well. Just make sure to set out a bowl of acidulated water (that's fancy chef speak for lemon juice and water) to keep them from turning brown. Shoot, that's kind of like an artichoke. This sunchoke name might not stick after all.
Choosing sunchokes might seem tricky at first — they're all irregularly shaped and hence all look a little different. The larger ones that look more like torpedoes are easier to slice thinly for chips and hold together better when fried. For roasting and puréeing, try to select sunchokes that are similarly sized so that they all finish cooking at about the same time. But no matter what, avoid greenish sunchokes and those with sprouts, a sign of age; always pick ones that are solid to the touch.
So that's pretty much all there is to know about sunchokes. Oh wait, just one more thing — according to Barbara Ann Kipfer, author of The Culinarian: A Kitchen Desk Reference, sunchokes contain a type of carb that might cause flatulence. So don't eat too many.