1. Combine ingredients in shallow, nonreactive pan and slowly reduce over extremely low heat. Mixture should be barely simmering. Continue until mixture is reduced to half its original volume. Let cool to room temperature and use immediately. 2. Serve over vanilla ice cream or panna cotta, on ripe pears or strawberries, with cheeses (especially, but not limited to, Parmesan), stirred into soups and drizzled over grilled steaks and pork chops—or anywhere else your food could use a hit of bright, sweet tang.