Combine mustard, basil, thyme, pepper, oil and worcestershire sauce.
Pierce lamb in several places with fork.
Place fat side up on trivet in 3 quart oblong glass baking dish.
Spread mustard mixture over lamb.
Chill 2 hours.
TO COOK BY COMBINATION: Insert metal acces sory rack.
Cook to desired doneness according to chart TO COOK BY CONVECTION: Insert metal accessory rack.
Cook to desired doneness according to chart