Preheat oven to 325C and place a rack in the middle of the oven.
Grind the coffee beans and peppercorns and mix with the salt and dried garlic to make the dry-rub. Rub the seasoning all over the Ribeye Roast with your hands.
Heat a skillet on medium heat for several minutes until very hot. Add the butter and let it melt, coating the whole bottom of the skillet.Carefully add the roast and brown for 1:30 minutes at a time on each side,using a pair of tongs to turn it. Do not move it other than to turn it.
If using an oven-proof skillet, transfer the skillet directly to the oven. Otherwise, transfer the roast to a shallow pan previously heated in the oven (no deeper than 2 inches, so the heat circulates optimally).Roast the rib eye for 25 minutes per pound. For a 5 pound roast, you'll want to roast it for about 2:05 hours.
Once done, remove roast from the oven, transfer to a cutting board and cover it loosely with a sheet of aluminium foil. Let rest for at least 20 minutes before slicing so as to allow for the juices to settle and distribute.