This Slow Cooker Prime Rib Roast Recipe is the easiest way to cook prime rib! Whether you're preparing a perfect prime rib for the holidays like Christmas dinner or other special occasions, this recipe is foolproof, with delicious flavor and texture, with a super approachable method that anyone can master! Serve it with our creamy horseradish sauce for an incredible main course.
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Preparing a holiday dinner is already enough of an undertaking. Looking for ways to free up the stovetop and oven can be challenging. Making slow-cooked prime rib in the slow cooker will save you so much effort and space. Plus, it results in an incredibly tender, juicy result.
No one wants to mess up an expensive cut of meat! Cooking the meat at a low temperature for a long time yields amazing flavor from the pan juices, and maintains the tender texture of the beef. Our step-by-step instructions will ensure you get this easy recipe right every time!
You may also like our melt in your mouth roast beef recipe, this sirloin tip roast in the slow cooker, or this Dutch oven pot roast.
For more holiday recipes, be sure to check out our Cajun seafood boil, this pineapple honey glazed ham, these baked crab legs, this buttery turkey recipe, or this butter poached lobster.
If you've got leftover prime rib - you've got to try our prime rib sandwich!
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❤️Why we love this recipe
- Approachable and easy. The slow cooker method makes cooking prime rib hassle-free and accessible for cooks of all skill levels.
- Made with staple ingredients. Everything you need for this recipe can be found at nearly any grocery store during the holiday season! You really only need a few pantry staples to make this flavorful main course.
- Perfect for special occasions. Prime rib is ideal for holiday dinners or special gatherings, adding a touch of elegance to any meal. It's always a showstopper!
- Great for a variety of meals and leftovers. Prime rib pairs beautifully with a variety of sides, like our steakhouse creamed spinach, truffle mashed potatoes, and creamy horseradish sauce. If you've got leftover prime rib the next time - you've got to try our prime rib sandwich!
- Minimal supervision required. This recipe frees up time to focus on making sides for the meal or to spend time with your guests, since the slow cooker does most of the work!
🥩Ingredients
Here are the ingredients we used for this recipe. You can find more information for substitutions below.
- Prime rib. Also known as a standing rib roast (if the bones are still attached) this is everyone's favorite steak cut (a ribeye) before it's been cut! It's a premium piece of meat! We usually prefer to use a boneless prime rib instead of one with the bone-in, but you can use whatever you'd like.
- Dijon mustard & horseradish sauce. These ingredients are optional, but highly recommended! For a very flavorful prime rib, we don't recommend skipping them!
Visit the recipe card for the full quantities and nutritional information.
✨Substitutions
Here are a few suggestions on additional flavors to try, or simple variations to this recipe.
- Swap the oil. If you don't have avocado oil, you can use a neutral oil that can stand up to high heat, like grapeseed or canola oil. We don't recommend using olive oil, as the smoke point is too low.
- No horseradish. If you don't have horseradish, just add extra Dijon mustard. It won't replicate the heat, but it pairs nicely with the prime rib.
- No fresh garlic. If fresh garlic isn't available, you can use 1-2 teaspoons of garlic powder as a substitute.
- No fresh thyme. If you don't have any fresh herbs aren't available, you can use dried thyme. Keep in mind that dried herbs are more potent, so you won't need quite as much.
- Beef stock. Chicken or vegetable stock can be used as a substitute. In a pinch, water with a beef bouillon cube can also work.
- Red wine braising liquid. If you want to infuse some extra flavor into the roast, you can swap out some of the beef stock for a red wine you enjoy the taste of.
- Add extra aromatics. If desired, add a few bay leaves, onions, or shallots to the slow cooker to infuse more flavor into the braising liquid.
- Dairy free. To make this recipe suitable for those who don't eat dairy, simply swap out the unsalted butter for a plant-based butter substitute.
✨Variations
🔪Prep work
- Season the outside of the roast generously with kosher salt and black pepper on all sides. (Image 1)
- If possible, let it sit, uncovered in the fridge for 12-24 hours before cooking to allow the seasoning to penetrate the meat, making it more flavorful inside and creating a crispier crust on the fat cap.
- When it's time to cook, allow the roast to sit out at room temperature for about an hour before searing. This will help promote a more even cook.
- While the roast is coming to room temperature, prep your ingredients!
- Allow the butter to sit out at room temperature to help it soften for the garlic herb butter.
- Mince garlic.
- Wash and dry the thyme sprigs.
- Measure out all other ingredients.
- Heat a large skillet over medium-high heat.
📋Instructions
To the hot skillet, add a few tablespoons of avocado oil to the skillet, and add the seasoned prime rib.
Cook for 4 minutes on the ribs side (where the bones would be), then turn and cook for 1 to 3 minutes each on the other sides, until browned, holding the roast upright in a skillet with tongs if necessary to hit all sides of the meat. (Image 2)
Remove from the skillet and set aside.
✨Pro Tip: Don't worry about cooking the meat all the way through. We just want to get it to get nice and brown on all sides to render out some of the fat and help build some flavor. Searing the meat also helps to lock in a lot of the moisture so that the meat will stay tender and juicy while it cooks.
In a medium-sized bowl, combine softened butter, fresh thyme, horseradish, Dijon mustard, and garlic with more salt and pepper. Combine well. (Image 6)
✨Pro Tip: Softened butter is easiest to work with here, so that you can combine all of the ingredients really well. If the butter is too warm, heat it up in the microwave at 50% power for 10-20 seconds, that should do the trick!
Add the beef stock and thyme sprigs to the slow cooker. (Image 6)
*You don't need much beef stock here, unless you want to use the leftover cooking liquids for French dip sandwiches, or gravy or something.
Transfer the prime rib to the slow cooker, ribs side down. (Image 7)
Cover and cook on the low heat setting for 3 to 5 hours or until just below the desired temperature is reached in the center, which is the thickest part of the roast! We use an oven-safe meat thermometer to monitor the temperature so that we don't overcook it.
*You'll want to the prime rib out 5-8°F below your intended temperature, as it will continue to cook as it roasts. For medium rare, this is around 125-130°F, and for our 5.5-pound roast, this took about 3 hours and 15 minutes. Each slow cooker is different, however, which is why you want to use a meat thermometer! See our temperature guide below for more info.
Transfer roast to cutting board. Cover roast loosely with foil; let stand for 20-30 minutes before carving, then cut into slices.
Serve with our creamy horseradish sauce, and your favorite sides, like this Steakhouse creamed spinach, some duck fat fondant potatoes, truffle mashed potatoes, Southern baked mac and cheese, and more! Enjoy!
What To Serve with Prime Rib
Besides a nice glass of red wine, you may be wondering what to serve with prime rib. We have tons of sides that would complement this delicious prime rib! Here are a few of our favorites!
♨️Temperature Guide
Please note, that we can't guarantee cook times when reaching these temperatures. It may take less time with a smaller cut, or more time with a larger cut, which is why we suggest using a meat thermometer. As mentioned, these are target internal temperatures, and the prime rib should be taken out of the oven 5-8°F before the target temperature is reached.
- Rare - 120°F - The center of the roast will be cool to warm, very tender, and a red to pink color.
- Medium rare - 130°F - This is generally considered the "perfect cook" on most cuts of beef. The center will be red and warm.
- Medium - 140°F - This cook will have a hot pink center, and the roast will be slightly firmer in texture. We find this to be a little over cooked.
- Medium-well - 150°F - The roast will be mostly brown and firm in the center.
- Well done - 160°F+ - Finally, this cook will have absolutely no pink color in the center. It will be completely brown, firm, and very dry. We don't recommend cooking your prime rib to this temperature.
✨Tips & tricks
- Select the right cut. Choose a high-quality prime rib roast with good marbling for the best flavor and tenderness.
- Season well in advance. Season the roast with salt and pepper at least 12-24 hours before cooking if you have time. This dry brining enhances flavor and helps form a crispier crust. This is a large cut of meat, so it will take a little bit of preparation to have it taste its best.
- Let the roast sit out at room temperature before searing. Let the roast sit out at room temperature for about an hour before cooking. This promotes a more even cook.
- Don't skip searing. Sear the roast on all sides in a hot skillet before adding the garlic herb butter mixture and placing it in the slow cooker. This creates a flavorful crust and locks in juices.
- Don't overcrowd the slow cooker. Ensure the roast fits comfortably in your slow cooker. Overcrowding can lead to uneven cooking.
- Use an instant read thermometer. To achieve your desired level of doneness, and avoid overcooked meat, use a meat thermometer. For medium-rare, aim for an internal temperature of around 130°F. The cooking time will vary depending on the size of your prime rib and your crock pot, so it's better to monitor the temperature rather than watch the time for the best results!
- Don't use too much liquid. Unlike other slow cooker recipes, prime rib doesn't require a lot of liquid. A small amount of beef broth will be enough.
- Let the meat rest. After cooking, let the roast rest for at least 20-30 minutes before carving. This allows the juices to be redistributed, ensuring tender and juicy meat!
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💭Frequently Asked Questions
Store leftovers in an airtight container in the fridge for up to 4-5 days.
To reheat in the oven: wrap the leftover roast in foil, then reheat gently in a 250°F oven until the internal temperature reaches about 120-125°F. This can take some time, anywhere from 30 minutes to 1 hour depending on how much beef is left. This helps to keep the beef juicy.
You can also reheat gently in the air fryer, on the stovetop, or in the microwave, but these will cook the meat faster and potentially dry it out, so be careful.
About ½ a pound, or 8 ounces is a good rule of thumb for meat per person. For those with big appetites, you may want about ¾ a pound or 12 ounces per person.
More Main Courses To Consider
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📖 Recipe
Slow Cooker Prime Rib Recipe
Equipment
- large slow cooker
Ingredients
- 5 pound prime rib roast (also known as a beef ribeye roast or a standing rib roast, bone-in or out)
- 2.5 tablespoons kosher salt, divided (to taste)
- 1.5 - 2 teaspoons coarse ground black pepper (to taste)
- 1-2 tablespoons avocado oil (as needed)
- 8 tablespoons unsalted butter, softened (1 stick)
- 1 tablespoon prepared horseradish (optional)
- 1 tablespoon Dijon mustard (optional)
- 10-12 cloves garlic, minced (1 head of garlic)
- 1 tablespoon fresh thyme, minced
- 6 sprigs fresh thyme
- 1 cup beef stock (as needed)
Instructions
- Season the outside of the roast generously with 1.5 - 2 tablespoons of kosher salt and 2 teaspoons black pepper on all sides. If possible, let it sit, uncovered in the fridge for 12-14 hours before cooking to allow the seasoning to penetrate the meat and create a crispier crust on the fat cap.
- When it's time to cook, allow the roast to sit out at room temperature for about an hour before searing. This will help promote a more even cook. Heat a large skillet over medium-high heat.
- To the hot skillet, add 1-2 tablespoons of avocado oil (as needed) to the skillet. Add the seasoned prime rib roast, and cook 4 minutes on the ribs side. Turn, and cook for 2-3 minutes on each of the other sides, until browned, holding the roast upright in the skillet with tongs if necessary. Once browned on all sides, remove from the skillet and set aside.
- In a medium-sized bowl, combine 1 stick of softened butter, 1 tablespoon fresh thyme, 1 tablespoon of prepared horseradish, 1 tablespoon of Dijon mustard, and the minced garlic with more salt and pepper. Combine very well until a paste-like texture is achieved.
- Slather the mixture all over the tops and sides of the roast, don't put it on the bottom of the roast, however.
- Add the beef stock and thyme to the slow cooker. You don't need much beef stock, about 1 cup is fine. Transfer the prime rib to the slow cooker, ribs side down (where the bones would be).
- Cover and cook on the low heat setting for 3 to 5 hours or until just below the desired temperature is reached in the center, which is the thickest part of the roast! We use an oven-safe meat thermometer to monitor the temperature so that we don't overcook it. *You'll want to the prime rib out 5-8°F below your intended temperature, as it will continue to cook as it roasts. For medium rare, this is around 125-130°F, and for our 5.5-pound roast, this took about 3 hours and 15 minutes. Each slow cooker is different, however, which is why you want to use a meat thermometer.
- Transfer roast to cutting board. Cover roast loosely with foil; let stand for 20-30 minutes before carving, then cut into slices. Serve with your favorite sides, and our creamy horseradish sauce, and enjoy!
- Store leftovers in an airtight container in the fridge for up to 4-5 days.
Save This Recipe! 💌
We'll email this post to you, so you can come back to it later!
Notes
- Select the right cut. Choose a high-quality prime rib roast with good marbling for the best flavor and tenderness.
- Season well in advance. Season the roast with salt and pepper at least 12-24 hours before cooking if you have time. This dry brining enhances flavor and helps form a crispier crust. This is a large cut of meat, so it will take a little bit of preparation to have it taste its best.
- Let the roast sit out at room temperature before searing. Let the roast sit out at room temperature for about an hour before cooking. This promotes a more even cook.
- Don't skip searing. Sear the roast on all sides in a hot skillet before adding the garlic herb butter mixture and placing it in the slow cooker. This creates a flavorful crust and locks in juices.
- Don't overcrowd the slow cooker. Ensure the roast fits comfortably in your slow cooker. Overcrowding can lead to uneven cooking.
- Use an instant read thermometer. To achieve your desired level of doneness, and avoid overcooked meat, use a meat thermometer. For medium-rare, aim for an internal temperature of around 130°F. The cooking time will vary depending on the size of your prime rib and your crock pot, so it's better to monitor the temperature rather than watch the time for the best results!
- Don't use too much liquid. Unlike other slow cooker recipes, prime rib doesn't require a lot of liquid. A small amount of beef broth will be enough.
- Let the meat rest. After cooking, let the roast rest for at least 20-30 minutes before carving. This allows the juices to be redistributed, ensuring tender and juicy meat!
- To reheat in the oven: wrap the leftover roast in foil, then reheat gently in a 250°F oven until the internal temperature reaches about 120-125°F. This can take some time, anywhere from 30 minutes to 1 hour depending on how much beef is left. This helps to keep the beef juicy.
- You can also reheat gently in the air fryer, on the stovetop, or in the microwave, but these will cook the meat faster and potentially dry it out, so be careful.
mk says
So how long should it take to cook a 12lb. bone in prime rib in a crock pot. I purchased a 10 quart capacity crock pot. Rib fits perfectly , just don't know how long to cook.
Briana says
Hi there!
We're thinking that since your roast is about twice as big as the one we made, it should take roughly twice as long to cook. We like our roast to be medium-rare, and it took about 3 hours and 15 minutes. For a 12-pound roast it could take anywhere from 6 hours - 9 hours. We can't say for sure, that's why we have to insist on using monitoring it with a meat thermometer so you don't over or undercook it!
Happy New Year!