In a small bowl, mix the salt, pepper, mustard, garlic and thyme together well. Place the roast on a platter and using your hands, generously season it with the mixture, patting it onto all sides. Cover with plastic wrap and refrigerate for up to 24 hours, or until you are ready to cook it.

Preheat oven temperature to 450 degrees F. Set the roast on a roasting rack in a roasting pan, fat-side up. If any of the dry rub is left behind on the platter, add it to the top of the roast. Place the roast in the hot oven and cook for approximately 1 hour or until the meat reaches an internal temperature of 125 degrees F (for medium-rare).

Remove the pan from oven and let sit for a minute or so before transferring the roast (using tongs, not forks) to a carving platter. Cover with a loose foil tent and let the roast rest for 10 minutes before carving.

While the meat rests, make the sauce: Skim off the fat in the roasting pan; place the pan over medium-high heat and when it's hot add the red wine. Using a wooden spoon, stir gently and loosen any browned bits on the bottom of the pan. When the wine has been reduced by half, add the stock and continue to cook, stirring, until the mixture is reduced by half again. Whisk in the thyme, salt and butter; pour into a small pitcher.

Carve roast to desired thickness and serve with the sauce on the side.

NOTE: Any leftovers make a delicious treat for a low-Glycal lunch. Serve on a bed of mesclun greens with crumbled bleu cheese. 314 calories/serving; GL=0, Glycals=0