Basil Vinaigrette for Roast Lamb

In this recipe a jus prepared from a roast leg, rack, saddle, or shoulder of lamb is finished as a basil-flavored vinaigrette. The resulting sauce may be served hot or cold. The recipe can be adapted by using roasting juices from other meats, different herbs, and various oils.

Because the only emulsifier is basil, a blender is used to quickly homogenize the mixture. Because the flavor of extra-virgin olive oil is compromised by the action of the blender, pure olive oil (which is vir