1 Start with the roast at room temperature (remove from refrigerator 1 hour before cooking - keep it wrapped). Preheat the oven to 375°F (190°C).
2 With a sharp knife make 8 small incisions around the roast. Place a sliver of garlic into each incision. Take a tablespoon or so of olive oil and spread all around the roast. Sprinkle around the roast with salt and pepper. Place the roast directly on an oven rack, fatty side up, with a drip pan on a rack beneath the roasting rack. This arrangement creates convection in the oven so that you do not need to turn the roast. The roast is placed fat side up so that as the fat melts it will bathe the entire roast in its juices.
3 Brown the roast at 375°F (190°C) for half an hour. Lower the heat to 225°F (107°C). The roast should take somewhere from 1 1/2 to 2 1/2 hours additionally to cook. The shape of the roast will affect the cooking time, by the way. So if your roast is on the long and narrow side, versus a more round shape, it may take less time to cook. So keep an eye on it. When the roast just starts to drip its juices and it is brown on the outside, check the temperature with a meat thermometer. Pull the roast from the oven when the inside temperature of the roast is 135° to 140°F (57°C to 60°C). Let the roast rest for at least 15 minutes, tented in aluminum foil to keep warm, before carving to serve.
To make the gravy:
Remove the dripping pan from the oven and place on the stove top at medium heat. Note that if you are pulling the roast out early, for rare or a medium rare level of doneness, you may not have a lot of drippings. Hopefully you will have some. If not, you may want to leave the roast in a little longer at even lower heat, 175°F, to ease some more drippings out of it. Add some water, red wine, or beef stock to the drippings to deglaze (loosen the drippings from the pan). Dissolve a tablespoon of cornstarch in a little water and add to the drip pan. Stir quickly while the gravy thickens to avoid lumping. You can add a little butter if there is not a lot of fat in the drippings. Add salt and pepper to taste. Mom adds some fresh thyme too if she has some. (See also How to Make Gravy.)