How would you cook a prime rib that is in two pieces?

December 23, 2019 9:39 AM

I couldn't get a large enough prime rib, so I had to buy two. The are bone in. One is about 5 pounds and the other is smaller - about 3 pounds. How would you cook them? We like ours to have a range of medium rare to blue rare. I intend to remove from the oven when the temp hits 126 ( I used to take it out at more like 120, but it's always way too much rare meat that way). Would you tie them together and treat as 1 roast? And if so would you sear all sides or just the outer-facing ones? Or would you treat them seperately, sear all sides of both roasts and take one out early? Help, my worst fear every Christmas is to screw up the meat!
posted by kitcat to Food & Drink (9 answers total)

Serious Eats just had an article on prime rib that uses a koji marinade -- which I expect you won't care about -- but in the course of applying the koji they disassemble the roast and then reassemble it for cooking, so perhaps the general sectioning-then-tying techniques may be useful for you?
posted by aramaic at 9:48 AM on December 23, 2019

We did this this summer because we couldn't get a large enough roast for the number of people expected. We cooked them separately. They'll cook a little faster and give you more surface area to work with.

We use the Serious Eats method linked above (not the Koji, just the roasting method.) Rather than taking one out earlier, I would be inclined to put the small one in a little later. Otherwise, you're trying to keep the small one warm while waiting for the larger one to be finished so you can give them both a blast of heat at the end. Still, keep an eye on the temperature of both, you might need to pull them at slightly different times.

The only reason I would tie them together is if most people prefer blue rare and you're trying to reduce how much surface area is exposed, which doesn't seem to be the case if you otherwise have to control for too much rare meat.
posted by jacquilynne at 10:19 AM on December 23, 2019

I do standing rib roast at least twice every year using the advice on this page. Perfect every time, and no worries (well, some...)


I would remove from the bone as it suggests. Tie each roast up individually, and cook them to temp. If one is smaller in diameter, it will go in after a while to finish together.
posted by humboldt32 at 10:55 AM on December 23, 2019

I'd not tie them together. Your group likes a variety of doneness: perfect! Cook one more than the other. And there are always a few people who want the end cut. You'll have four end cuts to satisfy anyone who wants one. Please everyone. Remember if one gets done before the other, a roast can sit on the cutting board tented with foil for 20 even 30 minutes and still be warm inside.
posted by tmdonahue at 11:32 AM on December 23, 2019

And if so would you sear all sides or just the outer-facing ones?

You've got some good advice above, so I will just nth it, but if you decide to tie them together (which I wouldn't), for food safety purposes make sure to sear all sides, because the inside faces otherwise won't get to the temperature to kill surface bacteria (which is the most important vector in cooking beef).
posted by General Malaise at 11:52 AM on December 23, 2019

Sear all sides, leave bones in, don't tie them together. A friend of mine literally just did as tmdonahue suggests above for a party with two roasts of different sizes, and all present agreed it was the best prime rib they'd ever eaten. Just monitor the temperature carefully on both roasts and you'll have a lovely meal!
posted by halation at 12:08 PM on December 23, 2019

I would use the Serious Eats reverse sear method. Low and slow. Put a probe into the smaller one, take it out when it hits temperature, then put the probe into the large one and do the same. Put them both back in together and blast them at 500 to put a crust on them.

I've been doing roasts this way since I saw Alton Brown do it and I've never gone back to the old way.
posted by bondcliff at 12:09 PM on December 23, 2019

Thank you so much! I have chosen the least stressful method suggested here. And who doesn't love the end piece - so true! I cook it according to Pioneer Woman's recipe and have done for 4 years now - maybe I'll switch things up next year, but I'm taking no chances. Merry Christmas!
posted by kitcat at 12:21 PM on December 23, 2019

You should absolutely just cook them separately, but this could totally be a job for transglutaminase (meat glue)! You could make one prime rib! And SCIENCE!
posted by Weeping_angel at 6:32 AM on December 24, 2019