Étoile's Creamy Sunchoke Risotto

Also known as Jerusalem artichokes, sunchokes impart a subtle taste not unlike their namesake's to this creamy, golden risotto. Even when thoroughly cooked, sunchokes provide a bit of fresh-tasting crunchiness to any recipe. This classic risotto, distinguished by the use of sparkling wine in place of still, which delivers a delicate twist on the palate, makes a fine first course or a light main course.  Arborio rice is a short-grained Italian rice named for the town where it is grown. Blessed with a high starch content, it is particularly creamy and chewy — two characteristics that make it an ideal flavor vector. Arborio rice is widely available in specialty-food shops and most fine supermarkets.  You'll have more than a half-bottle of bubbly left over after cooking, so keep the rest chilled for drinking. — Jeff Morgan Adapted from "Domaine Chandon" by Jeff Morgan.