Set oven temperature to 500°F. As the oven heats up, take the beef out of the refrigerator and allow it to come to room temperature.
On the cutting board, mince the garlic, sprinkle with the salt, and pound it with the side of your knife to a paste (you may also use a mortar and pestle). Press a couple more times to incorporate the rosemary after adding it. After transferring the garlic mixture to a small bowl, toss in the pepper and olive oil. Coat the roast meat with the spice mixture and place it in a roasting pan large enough to accommodate it comfortably.
Now is the time to put any thermometer probes or thermometers that you can see through the oven door.
Roast the beef for 15 minutes (5 minutes per pound; adjust time if your roast weighs more or less) when the oven is preheated. Turn off the oven after fifteen minutes, but don't open it!
In the event that you can take a temperature reading as it cooks: After the beef reaches 135°F for medium-rare (145–150°F for medium), remove it from the oven without stirring; this should take approximately 45 minutes (in my oven), but it may take up to 1 1/2 hours, depending on how effectively your oven maintains heat.
To ensure that the liquids are distributed evenly, take the roast out of the oven and let it rest for ten minutes before slicing it. Serve with a thin slice.