This easy cooking method allows you to cook PERFECTLY tender boneless beef roasts (from rare to medium-well) of almost any size, as long as the roast is at least 2-1/2 to 3-inches thick. The meat should be at room temperature for best results. Pork roast cooking time of approximately 25-30 minutes per pound should register about 145-150 degrees. Remove the boneless rib roast from the oven, transfer to a cutting board and tent loosely with foil 15-20 minutes. Sprinkle the top of the Cook time is based on the weight of each roast and desired doneness. I've used this method for 30+ years, and find it's a lifesaver when I'm having company and want a foolproof entree without the fuss! A 3- to 4-pound boneless prime rib roast, sometimes called a rib-eye roast, is the same amount of beef you'd get with a 4- to 6-pound two-rib roast. Approximately 15 minutes for searing the roast prior to roasting and approximately 15 minutes for the roast to rest before serving. Preheat oven to 325 degrees Fahrenheit. We suggest planning 30 additional minutes. Below is a cooking chart for ribeye roast. Remember you should always use an instant-read thermometer to check the doneness of a roast. DIRECTIONS. 5. At 6 to 8 pounds, you're getting the equivalent of a bone-in roast that weighs 8 to 10 pounds. If you'd rather go boneless, the roasts automatically get smaller. In method A because a temperature of 250 degrees is used the temperature will only rise about 2-4 degrees during resting time. Place pork in roasting pan.