Preheat oven to 325 degrees. Using a small sharp knife, cut small slits in roast, spacing them evenly over surface. Insert garlic slivers into slits. Rub roast with mustard; sprinkle with thyme and pepper. Roast until an instant read meat thermometer inserted into the thickest part of the meat registers 150 degrees for medium, about 1 hour 15 minutes. Transfer meat to a carving board and let stand for 10 minutes. Remove the string; garnish with thyme sprigs. Carve into thin slices and serve.
|