Finishing pre-cooked prime rib, day-of?

Question

I’m ordering a 6lb. bone-out prime rib roast from a local butcher. I want to have them season and (mostly) cook it for me in their rotisserie on Christmas Eve (pickup at 4pm) so I can just finish it quickly in my oven Christmas Day (12pm).

I have a couple questions:

1. what internal temperature should I ask them to cook? Thinking 110°.
2. what’s the best method to finish it? I’m thinking rest to room temperature then 375° uncovered oven roast until 120° internal to get a crisp herb crusted exterior (as opposed to a foil tent or foil wrap).
3. am I insane? Should I just roast it all myself?

Thanks!

Answer 1

Two stage cooking is generally not a safe practice unless the food comes to at least 130-140F during the first stage, held there an adequate amount of time to kill off bacteria, then is chilled quickly, and then reheated relatively quickly. Commercial food service has a lot of fairly complex rules dealing with these sort of "pre-cooked" and reheated situations, because they are one of the places where it's most likely to cause foodborne illness.

Since you likely wouldn't want to go to temperatures that high (and I don't blame you), I'd recommend cooking it all yourself at one time for safety reasons.

Also, aside from safety concerns, I agree with moscafj's comment: I'm not sure what the purpose would be here. Is it to get some benefit from the "rotisserie"? It's possible to get somewhat similar effects by roasting slowly (at low temperature) at home, even without a rotisserie.

EDIT: Since the OP has identified the goal as decreasing cooking time, I agree with AMtwo that this process won't help. I'd only add to AMtwo's answer that it might actively hurt the quality of the final result, as both the butcher's rotisserie and OP's relatively high-heat oven temperature will likely cook the outer layers of the meat further, while leaving the interior very rare. Doing this twice will actually compound this problem, so if the goal is a rare roast (as I'm guessing from the target temperatures mentioned), this will actually result in a thicker layer of more "done" meat near the edges with more time to dry out. Better to just cook it once.

Answer 2

Your goal is to reduce cooking time. Having your roast previously partially cooked won't help.

Ultimately, on Christmas Day, you'll need to heat a 6-lb roast from <40°F (fridge temp) to >120°F(cooked temp). That will take roughly the same amount of time whether it's raw or partially cooked. There's some variance, but not enough to matter on your cook time.

The only way you might save time is if you have your roast FULLY cooked, then on Christmas Day, you could reheat to a lower temperature than it was previously cooked to. This is essentially how most hams are sold in the US--they are fully cooked and just need to be reheated to serve.

Precooking and reheating doesn't work as well with beef as it does with ham.

Personally, I'd simply get the roast uncooked, and fully cook it myself on Christmas Day.

Answer 3

If you want to do two stage cooking, the only option that's safe not to mention tasty is to cook it sous vide.

You could cook it to the desired finishing temperature (I like 132-135, but your preference may vary) for an extended amount of time (say, 6 hours, though Prime Rib can go quite a bit longer if preferred). Then you can either just finish it directly (if you start the sous vide Christmas morning or just before bed the night before) or you can chill it (quickly!) and then finish it later (especially if you want some of the roasting benefits that you lose with sous-vide).

Sous vide will cook it safely, evenly, and will not dry out the outside significantly. That way, when you do finish it, you're just adding a first layer of more done meat - not a second layer.

I do recommend slightly higher temperature for Prime Rib than you would for a Strip or other similar cut; Prime Rib will hold a better texture just slightly more done. I usually hit the mid 130s for mine (while I'd hit 130 or less for a Strip).

https://recipes.anovaculinary.com/recipe/sous-vide-prime-rib is one example of a recipe for doing just what you're thinking.

Do note that cooking a whole Prime Rib sous-vide is a bit challenging due to the size - most people (myself included) would have trouble finding a big enough container for the water bath, not to mention probably go over the recommended meat weight for the immersion circulator (which might break the circulator - it did for a buddy of mine). You could break up the roast into a few pieces and do them separately, perhaps even chilling one while you don't chill the other just to see which one you like better!

Answer 4

Goal is to reduce cooking time day-of.

Your plan is not helpful for that. Cooking time is all about heating up the food (and/or evaporating water), not putting energy into some chemical reaction. Cooking is slow because it takes time to get the inside from fridge temp to your target, and food doesn't conduct heat very efficiently.

And for a rare roast like this, not about time-at-temperature either like BBQ where you're converting collagen to gelatin. And stopping at 110F is too low for anything to happen anyway.

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On the day of, before putting it in a real oven, warm it some (not cook) in a microwave on medium power (like power level 6 out of 10 on a 1500W oven for example) for several minutes to heat the meat somewhat uniformly. (Sorry I don't have a solid estimate for this, and of course it depends on the absolute power of your microwave.) Maybe 10 to 15 minutes, and maybe on even lower power than that. You need time for heat to transfer from hot spots so they don't actually cook. Check for hot spots after 10 mins, and maybe put it in for another few minutes if it's not very warm yet.

To avoid hot spots cooking on the surface of the meat, you'll want a microwave with a turntable. Maybe even turn the meat during some microwave time.

Then stick a probe thermometer in and roast as normal, starting from a meat temperature of maybe 90F. You just want to warm it, not even close to cook any of it with the microwave. And let it rest some to even out hot spots that were close to starting to cook, before you put it in the oven.

Your goal with the microwave step is to get heat energy into the middle of the roast without starting to even brown the outside. Microwave ovens can do this somewhat better than hot air because microwaves penetrate slightly into the meat, into the wet part, where heat can more efficiently conduct inward without drying out the outside. You have to be careful not to actually cook parts of the meat, just get it up to around room temp.

A roast for a special occasion is probably not the best time to experiment with this, and be sure to read the comments on this answer. I think they're being too pessimistic and are basing their opinion on actually cooking meat with a microwave, not just warming it up. But maybe I'm wrong and there's no way to usefully do this.

I have done this with steaks before pan-searing with good results: less time in the pan is needed, and you still get a browned outside layer and a nice rare or medium-rare inside. Ideally you can get the inside medium-rare with less of a well-done layer outside it. (A significant part of the cooking of the inside still comes from traditional cooking; you're just starting with a warm piece of meat instead of fridge temp).

If you're a little aggressive with the microwave you'll get some cooked patches on the outside (especially with a steak; a roast is maybe more resistant to that.) If you see that, stop the microwave and let it rest for a few minutes to come closer to thermal equilibrium before going into the regular oven.

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A roast is done when the centre reaches a high enough temperature. If it starts uniformly at fridge temp, cooking by roasting in a hot oven heats it up by heat transfer from air to the outside layer of meat. This is slow, so it takes time even for the outside to heat up and start heating the inside by conduction.

This hot air also dries out that layer, letting it get significantly hotter than inner layers (and letting browning reactions happen forming a crust). This is why you want to roast at a low temperature so this doesn't go too far before the cold centre of the meat gets up to temperature.

Starting with the meat hotter some/all the way through (closer to thermal equilibrium than you'd get from oven heating) means not as much heat energy has to be conducted all the way from the outside of the roast into the middle with dry heat, so you'll have less of a well-done layer.

When you put in the probe thermometer, you'll get some idea of how much temperature difference you have between the outside and inside. If it's significant, perhaps let it rest a couple minutes. Not more; the meat will be right in the danger zone for bacteria so you should get it heating again quickly.

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This is not something I've tried with a roast, only steaks. It's simple physics, though.

Other ways of heating meat without cooking the outside include sous-vide. In that case heat transfer slows down as the meat temp approaches the water bath temp, so you can use it to get the meat all the way up to desired temp. This is not the case with microwaves because they apply near constant power to a layer around the outside, and not evenly. This is why you have to stop before any the meat is even close to fully cooked, and let the temperature even out.

(Do note that microwaves don't really penetrate very deeply, but they can get about a centimeter in so heat has a head start conducting into the centre of the food.)