How to cook a prime rib in an electric roaster – easy and perfect every time. With the holidays upon us you may be planning out your Christmas dinner menu, like me. I traditionally make a ham with my family’s secret sauce, and this year is no exception. However I have discovered how to make the perfect prime rib in an electric roaster and have decided this decadent delight must be part of our meal this year too. Prime rib is my husband’s favorite meat so learning to make it well has been a goal for me; not to mention ruining a cut of meat the price is terrifying!
You can make a worry-free, perfect, prime rib in an electric roaster and everyone is going to love it!
How To Cook A Prime Rib In An Electric Roaster
Now first things, first, I’m assuming you already own an electric roaster but if you don’t I can recommend the Oster 18 qt model (great for roast turkey too). You can probably do this recipe in the oven with similar results, but I have only done it in a roaster. You will also need a meat thermometer. It is important not to open your roaster during cooking so I recommend an electric meat thermometer like this one that can be read outside of the roaster. Make sure your thermometer has fresh batteries!
Why I Prefer to Cook Prime Rib in an Electric Roaster
Fear. Yeah, totally fear. No, really, that is why I originally did it this way. I felt like the roaster had more consistent temps that my old oven and with it self-basting I knew I couldn’t dry it out! I love using my electric roaster, especially for big holiday meals because it frees up space in my oven for other baking and side dishes. It was worth the investment and pantry space it takes up!
A Few Notes Before We Make This Delicious Prime Rib in Your Electric Roaster
Before we get to the recipe it most be noted that you should NEVER, ever, open the roaster during cooking. That’s why the meat thermometer is so essential; you’ll know it is done without lifting to look. A roaster self bastes the food but everything gets disturbed when the lid is lifted. Let everyone in the house no – NO LIFTING THE ROASTER LID!!! The same goes for your oven, if you choose to do it in there; do not peek until the meat thermometer says it’s done. The roast should take about 13 – 15 minutes per pound to cook, depending on how you like your meat.
When you cook prime rib you can use these meat temperatures for guidance on how well done you want it. Most people associate prime rib with medium rare but not everyone likes it that way.
Prime Rib Meat Doneness Guide:
You can set your meat thermometer to beep when your meat hits the desired temperature.
130ºF – Rare
135ºF – Medium Rare
140ºF – Medium
150ºF – Well Done
Prime Rib In An Electric Roaster – The Recipe
Delicious and Easy Prime Rib in an Electric Roaster
Ingredients
- 6 - 8 lbs Prime Rib Roast
- Sea Salt or Kosher Salt to taste
- 2 tsp or more of Black Pepper
- 1 to 2 tsp Dried Rosemary
- 1 to 2 tsp Dried Thyme
- 5 - 6 cloves Minced Garlic I used jar garlic because I didn't have my own available
Instructions
- Take the roasting rake out of the roaster and set aside.
- Plug your electric roaster in, lid on and pre-heat to 325 degrees F.
- A lot of cooks will tell you to leave the roast on the counter for up to 2 hours to allow it to come to room temperature. I don't do that but it is up to you.
- Open your roast and place it on the roasting rack so you can just lift it into the roaster once it is prepared.
- We aren't going to be super precise with the seasonings - trust me, it is going to be ok! However you are going to get your hands all over uncooked meat so please take safety precautions to keep from doing any cross-contamination.
- Liberally salt the roast on all sides.
- Now evenly spread out the black pepper, rosemary and thyme over all sides of the roast.
- Really press those seasonings into the meat, including the salt.
- Next I like to spread the minced garlic on the top only but you can try to spread it around if you want.
- Carefully life the rack with the prime rib into the pre-heated electric roaster. You do not need to add any liquid to the pan.
- Put the meat thermometer dead center in the meat; and make sure it is on and set to your desired doneness.
- 130ºF - Rare
- 135ºF - Medium Rare
- 140ºF - Medium
- 150ºF - Well Done
- Replace the lid. Leave the roaster at 325 degrees F and DO NOT OPEN THE LID!
- Once done remove the prime rib from the electric roaster and allow it to rest for 15 - 20 mins.
We like our prime rib with a creamy horseradish sauce that you can make in a jiff!
DIY Fast & Easy Peasy Creamy Horseradish Sauce
Ingredients
- 1 cup full fat sour cream
- 1/3 cup prepared horseradish
- Salt and Pepper to Taste
Instructions
If you find it too strong you can add a bit more sour cream until it is to your liking.
- In a small bowl whisk all your ingredients together and allow it to chill 20 - 30 minutes in the refrigerator.
- Serve
I hope you find cooking a prime rib in an electric roaster as easy as I do. Enjoy the rave reviews on this meal! Great served with mashed potatoes, and a simple green vegetable.
Be sure to check out these other popular recipes!
Southern Ham & Beans Recipe with Cornbread
Play for pound prime rib in the electric roaster will only take an hour? To cook medium to medium well
It does cook a lot faster in the roaster but always give yourself a little extra time the first go!
This looks perfect. I’m having 13 people on Christmas Eve 5 Course meal. Is the roast boneless? How much should I buy? I see 1 pound per person and 1/2 pound per person.
If it is bone-in you definitely want to go 1 lbs per person. You can use this recipe for boneless or bone-in – use your thermometer to know if the meat is at your desired doneness.
I’m so excited to find this recipe, there are not a lot of prime rib recipes for a roaster oven, that I’ve been able to find. What I’m curious about is, most recipes for a prime rib that are done in a regular oven say to increase the heat to 425 – 500 degrees for the first 15 minutes to sear the meat. But all the roaster recipes I’ve see do not have you do this. Just curious if you knew the reason why this is?
I’m not sure but I’ve never need to do this with the roaster. Maybe it is the size difference.
I have 2 – 5lb prime rib roast,. How long will it take to get them medium rare!
The only way to really do them correctly is with a meat thermometer; you want 135ºF fir Medium Rare. Generally prime rib should be cooked 13 – 15 minutes per pound.
yes yes yes! I cook larger (17 – 20 lb) 6-7 bone rib roast, and sear at 425 for 20 minutes prior to dropping temp to 325 for 12-15 min/lb . Also recommend a dig. meat thermometer so inside temp is just where you want it! I do 145 deg. pre standing for a nice medium roast that has well done ends for those not inclined for a little color!
Curious, Are you saying you sear the prime rib in the roaster oven? And based on recipe saying to not open the lid, you just turn the temperature down after 20 min?
Do the vents in the lid affect the roasting time/temperature?
Cooking ac10lb boneless prime rib in the electric roaster ; how long should this take ?
The roast should take about 13 – 15 minutes per pound to cook, depending on how you like your meat. I have the temps for how done in the post.
You must remember that there is carryover cooking that occurs after you pull your roast from the oven. I would recommend pulling your roast when its ~10deg F cooler than your preferred doneness as it will come up to the target temp while it rests. That means you want to pull the roast at around 118-123 degrees for medium rare.
I need to cook about 21 lbs of Prime Rib. Can I put 2 (appropriately 7 lb) pieces in one Roaster? We will be traveling (Camping) & need to plan ahead. Thanks
Shouldn’t be a problem.
Has anyone cooked this recipe? I’d hate to use for a holiday and find out that it didn’t come out or taste good!
Every Christmas! I do use a salt n pepper rub the night before and take out of fridge about 90 minutes prior to searing. Prime in a roaster is the only way to fly!
Any pictures of the roast when done? Is there a crust on the outside?
Truly I like the simple instructions but I am curious if anyone has cooked this in a roaster as well.
Any thoughts about cooking it at a slower temp for longer?
Does it produce a lot of juice to make the au jus?
It does get a crust, but not the same as an oven. I have never tried it any other way, I was too scared to mess with an expensive piece of meat! lol Lots of juice!!!
I had some great success at Thanksgiving and just wanted to confirm I (mostly) used your advice and very much appreciate it.
I had an 8lb bone in cut. At 325 it took about 2 hours and 20 minutes to get to an internal temp of 120. Now I read on many other sites to pull at 120 internal temp to get it to rare in the middle/medium rare on the sides…that it would increase 10 degrees resting…and at 135 internal you may have ruined it.
I found 120 internal was perfect for a rare cut, only medium rare was the outer inch on each side. 3 of 4 adults like rare so this worked great, next time I’ll leave until 125-130 internal to give my wife some medium outer edge cuts (she from Louisiana and they like well….ugh!).
But it was delicious.
It didn’t form a crust for me and I seared a little before hand. Also I went light on salt which may have affected the crust and the lack of juice it put out. Again, my rub was still delicious and I had enough drippings to supplement my au jus I made prior. Next time, I’ll salt heavier and re-season after searing. Small points but I’m always looking to improve.
All in all, it was a huge hit. It was a beautiful piece of meat and was super flavorful. Was so so SOOOO simple to cook in the roaster.
3 hours to room temp
Herb Garlic rub
15 min to sear
2.5 hours at 325, only checked the internal temp – never opened
20-30 rest
No need to cut the ribs off as they fell off once untied
Slice and serve
Absolutely delicious!
Thanks!
Marc I love reading these comments! I know a prime rib is a BIG investment and I am so glad my instructions / recipe helped you.
I have never used an electric roaster for prime rib. I have a 7.5 bone in. When you say sear, do you do it on top of the stove or turn your roaster on high for 20 minutes and then turn it down to 325? We like medium rare so how long should I cook it.
Thanks.
I am going to be trying this just one question. I have always seared the prime rib before cooking in the oven , I don’t see that in you recipe is that still recommended to do in an electric roaster or not? Thank you.
I don’t do that but if you want a browner “crust” that would be helpful.
I tried your “Electric Roaster” recipe for the first time at our family dinner for 9 people on Christmas Day. I got a 9.3 lb. bone-in rib eye roast from Costco. (great cut of meat, .. much better than I found at my local supermarkets) I took your advice and got a ThermoPro TP-16 meat thermometer from Amazon. I took the roast from the refrigerator and seasoned it with salt, pepper, garlic and herbs, 2 hours before cooking. When I inserted the temperature probe it read 50 degrees internal temperature. I put the roast on the top rack of the oven in the stove at 500 degrees for 15 minutes before moving it to the electric roaster. I set the desired temperature at 130 degrees and a 2 hour cooking time using the estimate of 13 minutes per pound. The thermometer rang 130 at 1:59 minutes. I moved the roast to the carving platter and left the thermometer in place to monitor the temp. After a 30 minute “resting period”, I was surprised to find the temp had continued to rise to 147. When cut, the end slices were well done, .. the second slice was medium, .. the third, fourth, and center slices were medium-rare. This was fine, as a couple family members were “pink-adverse” and welcomed the end slices. One guest who wanted rare had to settle for medium-rare. The roasting pan produced 1.5 cups of juice which was used by some as Au Jus. The rib-eye roast was a big hit for a family long been accustomed to a Christmas dinner of either turkey or ham. Your recipe worked like a charm and the result was delicious. The only thing I would do different next time would be to remove the roast at 120 so the temp at the end of the resting period would be closer to 135. Thanks for making me look good.
Oh, so glad to read this! Glad you looked like a pro!!! 😉
Oh, I love prime rib! I cook mine every year in a roaster, it’s the only way to go! It’s so fun to see different spices, thank you for your ideas!!
It is definitely fool-proof. And you can’t beat the flavor!
Delicious!
Glad you liked it!
This looks so good! Thanks for this awesome recipe.
Would love to hear how it works for you!
Hi, My question is when you cook it 13-15 minutes per pound, I’m assuming from comments that makes it medium rare in the middle? (I know I need a thermometer) just trying to figure timing on the whole dinner. I’ve done turkeys in my roaster but never a prime-and yeah, I’m a little nervous!
That’s definitely an estimate for medium rare. I wouldn’t do it without a thermometer.
Thanks so much for this recipe. It is wonderful. I have never attempted to cook prime rib in my 63 years. This is so easy. We decided to have prime rib for Christmas this year. My husband said we should do a trial run. Made it today and it was the best. Again thank you so much and Merry Christmas to all.
Merry Christmas to you and your family too. Prime Rib has become a Christmas tradition here, I’m so glad you enjoyed it!
What if you do not have a thermometer and its to late to buy one
Go with the 13 – 15 mins per pound for about medium.