Put all ingredients (except olive oil & leg of lamb) in food processor. Use steel blade and add the olive oil slowly until ingredients from a smooth paste.
Cover lamb entirely with paste and refrigerate for 1 hour. (Reserve some marinade for a sauce.)
Preheat oven to 450°. Roast lamb for 10-12 minutes PER POUND for medium rare.
If you are using a metal thermometer, cook until it registers 140°.
Remove lamb from oven and let stand for 20 minutes before slicing.