I'm cooking a 21 lb prime rib and want it rare. How long should I roast it for (and at what oven temp)?

I'm doing a very simple salt and pepper rub, no fancy crusts. Thanks!



bigpan December 24, 2011
Is the bone on or off - check various sites for time temp you prefer - but- invest in a thermometer and pull the roast out at 120F ... it will continue to cook while resting. Rest tented for at least 20 minutes. I encourage horseradish.
Kristen M. December 24, 2011
For a roast that big, you'll probably want to cut in half -- if you use the Ann Seranne recipe Amanda shared above, you can follow the timing on the roasting chart for 11-12 pounds and roast them in the same oven.
Flavor D. December 24, 2011
Check out this segment from the MSL Show this week with Molly Stevens on roasting prime rib. http://www.marthastewart.com/873666/standing-rib-roast-prime-rib-yorkshire-pudding You can adapt the recipe to season as you prefer, but the guidelines for roasting are excellent. You can find a video link to the segment on the left margin of the page. Good Luck and Merry Christmas
Amanda H. December 24, 2011
Here's a great recipe for it with foolproof technique. http://www.food52.com/recipes/15387_ann_serannes_rib_roast_of_beef
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