When I first developed this vanilla ice cream recipe, more than a few folks thought the peach preserves were a crazy addition. But consider this: Jams and preserves contain pectins, which are gigantic molecules that have considerable gelling power. Including just a wee bit not only smooths out the ice cream's texture and elevates the subtler flavor of the vanilla, it can also actually delay melting a bit. And as you know by now, salt, in small amounts, can turn up the volume on almost any flavor. I include a pinch in most dessert applications.Both U.S. standard and metric measurements are listed, but for consistent results, go metric.This recipe first appeared in Season 1 of Good Eats.