This is more of a special marinade that is quite suitable for lamb. Submitted to ODCW way back in the year 2000.
Large rolled or boneless leg of lamb, also works well on a rack
1/8 cup dry vermouth
1/2 cup olive oil
Fresh chopped rosemary about 1 tablespoon after chopping
1 teaspoon Montreal Steak Seasoning
Kosher salt to taste
Mix all ingredients, add lamb and pour mixture into a large seal-able plastic bag. Close tightly and marinate overnight. Turn frequently.
Grill until a meat thermometer arrives near 140 degrees F for rare-medium or 160 degrees F for medium-rare.
Attributed to: Pryce Haynes a great fan of Montreal Steak Seasons. Me too.