But as I learned on a recent visit to Austria, sweet wines—meaning wines with high levels of residual sugar, made from grapes left hanging on the vine until late in the season, and often served with dessert—are regarded with as much reverence as Sachertorte. And for good reason. The wines I sampled were complex and surprising, demanding complete attention even after a full meal. They swirled like amber-colored maple syrup in the glass, releasing a honeyed perfume that was the olfactory equivalent of clearing away the dinner dishes, scraping the crumbs from the tablecloth and plunking a majestic pie in the middle of the table. The wines' sweetness, while powerful, was calmed with generous notes of fruit, and tempered by a slightly bitter finish—a gift from the botrytis or "noble rot" fungus that, in the right temperature conditions, develops on grapes at the end of the season and helps concentrate their flavor.