Perfect Medium Rare Prime Rib Roast

Total Time
1hr 35mins
Prep 5 mins
Cook 1 hr 30 mins

Simple, basic, how-to recipe. Meat thermometer required. Cook to internal temperature, not elapsed time. Time is approximate for a 5-pound roast. Any size roast will do, just cook to the correct internal temperature. Add 20 minutes for resting time.


  1. Preheat oven to 450°F.
  2. Pat the rib roast dry with a paper towel or napkin.
  3. Smear the cut ends of the roast with the butter. Place the roast (ribs down or fat side up) in roasting pan.
  4. Sear the rib roast for 15 minutes at 450°F, then turn the oven to 325°F for the rest of the cooking time. Every 1/2 hour, baste the cut ends of the roast with the fat accumulated in the roasting pan.
  5. Cook until rib roast reaches an internal temperature of 120°F Remove from oven, cover loosely with aluminum foil, and let sit approximately 20 minutes. The roast will continue to cook as it sits. Serve when the internal temperature reaches 130°F.
Most Helpful

This was great for Easter dinnner, I did add salt & pepper and onion and garlic powder. My 3 pound roast was cooke to 165° and came out medium in the middle and medium well in the ends. Thanks for posting CipherBabe. Made for PAC Spring 2010.

ElaineAnn April 04, 2010

Fantastic! Used with Roast Beef Slather on a little 2 lb sirloin roast. 15 minutes @450 degrees F then 20 minutes @325 degrees F yielded a perfect medium rare roast. Will keep this to use again & again. Thank you CipherBabe!

Buster's friend September 27, 2007

Tried this recipie, for Easter Dinner, and it was the best prime rib I've ever had. We had a large crowd so I needed a large roast. cooked it according to the recipie and it came out fantastic. Was hoping to have some leftovers but everyone enjoyed it so much they were asking for seconds ! I will use this recipie and cooking directions from now on. Can't say enough about the recipie.

walter.weis March 28, 2016