I have tried the slow cook method, but I like the caramelized outside this method provides. If you start the roast at 450 degrees F (235 degrees C) for the first 30 minutes and then reduce the temperature to 325 degrees F (165 degrees C), allow about 13 to 15 minutes per pound for rare. The roast will keep cooking when you take it out of the oven to rest, let rest for 15 minutes before carving. Perfection.