In a mortar with a pestle, combine all the ingredients for the rub and grind together finely. Lightly coat the beef with the oil, then coat the beef evenly with the rub. Allow the roast to stand for 30 to 40 minutes before grilling. Place a foil pan beneath the cooking grates to catch the drippings.
Prepare the grill for indirect cooking over medium-high heat (400° to 500°F).
Prepare the grill for cooking over medium-high heat (450°F).
Place the beef, bone side down, on a grilling rack and grill over indirect medium-high heat, with the lid closed, until an instant-read thermometer inserted into the thickest part of the roast (not touching the bone) registers 125°F for medium rare (or until cooked to your desired doneness), about 1 hour for medium-rare.
Place the beef, bone side down, on a grilling rack and grill over medium-high heat, with the lid closed, until an instant-read thermometer inserted into the thickest part of the roast (not touching the bone) registers 125°F for medium rare (or until cooked to your desired doneness), about 1 hour for medium-rare.
Remove the beef from the grill to a cutting board, tent with aluminum foil, and let rest at room temperature, indoors, for about 20 minutes. Carve into thin slices.
