This boneless keto prime rib roast recipe comes out perfectly even if you’ve never made prime rib before! The exterior has a flavorful golden brown crust which, when it’s sliced, reveals a butter tender interior that’s the most gorgeous medium rare that you’ve ever seen. Just add cauliflower mash (aka cauliflower mashed potatoes) and some roasted asparagus for an incredibly romantic dinner that’s perfect for your keto diet.
For this recipe you’ll need: 5 pounds boneless prime rib roast, kosher salt, cracked black pepper, garlic powder, onion powder, herbes de provence, olive oil, and a roasting pan with a rack.
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Keto Prime Rib Roast
A boneless prime rib roast is the perfect romantic dinner because it’s just so dang easy! There’s not a lot of fuss involved with getting it on the table and if you follow the directions, it comes out exactly right every single time. Once your romantic dinner is over you’ll have plenty left to add to your meal prep menus, too!
I always thought that prime rib was hard to make so I was totally shocked at how easy it was. I rubbed the beef down with my olive oil and herb mixture the night before I was ready to cook it and that was all the preparation it needed. The flavor of the herbs soaked into the meat so that when it was cooked every single bit was juicy and full of flavor!
I really had only had prime rib roast at restaurants and on cruises prior to my making it myself. I figured it was too complicated for me. In my mind it was relegated to the same “don’t cook this at home” shelf as live Maine lobster. That is something I will never ever cook because I can’t kill a live thing. Call me a wimp, call me a hypocrite but if I have to kill it or starve, I’ll be starving, thanks.
I always hear about how great cruise ship fare is but I have to tell y’all, I’ve just gotten back from my fourth cruise and I’ve never been overly impressed with the food.
Seriously though, I’ve been on three major cruise lines and some are better than others but none of it has been anything that I’d go crazy over. By the last few days of vacation I can tell that it’s time to restock the kitchen. The last cruise was a little different because I got sick so I was on a diet of melba toast rounds and diet coke for the last three days.
All of that to say that prime rib roast is so easy to make there’s no real reason just to have it at restaurants. I promise. With Easter and Mother’s Day and other great holidays happening, this prime rib recipe is perfect for a romantic or celebration dinner that keeps things nice and low carb.

What makes prime rib so good?
There always seems to be a lot of mystery surrounding prime rib roast. It’s almost as if it’s one of those royalty only dishes served only to people that live in castles and sit on thrones. The truth is that, although it is an expensive cut of beef, it’s so easy to make and so versatile there’s no reason not to have it as often as you like. Here are some prime facts about prime rib:
Where does prime rib come from?
Prime rib is a cut of beef that’s cut from the back of the upper rib section. It’s sometimes called a standing rib roast and is made up of seven ribs, which can be cut smaller or made boneless (as in this recipe). Being called “Prime” traditionally means that it is USDA graded as Prime. That is the most heavily marbled aka fatty beef. This makes it the most desirable and thus, the most expensive. USDA Choice is the next level. It’s less expensive but also has less fat. The most affordable is Select. It doesn’t have as much fat.
When choosing a prime rib, I ask the butcher at the meat counter for the “chuck end” which is from ribs 6-9. They tend to have more fat in the middle. The “loin end” is from ribs 10-12 and has a little less fat in the middle. They can remove the bones for you which makes things easier.
How much prime rib per person?
When planning for your holiday or romantic dinner, a pound for prime rib per person is a good rule of thumb. For example a 4-6 pound prime rib roast has about 2 ribs and will serve about 4-6 people. For a bigger gathering, an 8-10 pound prime rib will serve about 8-10 people and has 4-5 ribs.
I love to get more than needed for that first meal as the leftovers are simply awesome.
What makes prime rib so good?
Prime rib has a large round or “eye” of meat in the center which is marbled with fat. The entire roast is also surrounded by fat. While the meat cooks the fat liquefies and adds flavor and juiciness to the meat. Also, since this comes from a part of the animal where the muscles are not used much it is extremely tender. So don’t let the butcher cut off the “fat cap” that covers the meat.
How long should I cook prime rib roast per pound?
If you follow the instructions here it will be a perfect medium rare but as a rule of thumb about 15 minutes per pound. I recommend cooking by internal temperature. Rare is 120-125 degrees fahrenheit. Medium rare is 130-135 degrees fahrenheit. By using a meat thermometer when you are cooking it will eliminate mistakes. Removing the roast from the oven when it hits 120 degrees fahrenheit is what I do. That’s because it continues to cook while resting which I do by loosely tenting it with aluminum foil.
How long should I let the prime rib roast rest after cooking?
About 15 to 20 minutes is enough time for the meat to finish coming to the proper temperature and for the juices to settle into the roast. That’s because when you cook meat, the proteins of the meat actual squeeze out the moisture. Resting it will let those juices get reabsorbed by the meat. I recommend letting it rest until the temperature drops to about 120-125. Then when you slice it, those wonder juices don’t end up on the cutting board. Instead will end up in your mouth.
What to do with prime rib roast leftovers
If you create a cozy dinner for two with prime rib you’re going to have leftovers! No problem – I’ve got you:
- Use the rarest portions in the center as prime rib another time. Since the center is often more rare than the ends it warms up well without overcooking. To use – thaw overnight in the refrigerator then add to a oven safe baking dish with 1/4 cup of beef broth. Cover with foil and heat in a 300F oven for 15 minutes.
- If you have an electric meat slicer prime rib makes the best roast beef sandwiches ever.
- Slice thinly and warm up with gravy to serve over cauliflower mash.
- Use it for beef pozole verde.
- Use it in place of chicken in this pot pie.
- Cut it in chunks for stews.
- Use it in wraps.

Romantic Dinner for Two
If you’re thinking of putting together a romantic dinner for two I don’t think you can do much better than this prime rib recipe. Here is a possible menu:
- Appetizers- Spinach and Artichoke Stuffed Mushrooms Low Carb Yum
- Main – Prime Rib
- Horseradish cream. Horseradish sauce is low carb normally, just make sure to check the label on the bottle.
- Vegetable – Slow Cooker Pepper Jack Cauliflower All Day I Dream About Food
- Vegetable – Southwestern Broccoli Salad
- Dessert – Pecan Cheesecake
- Cocktail – Dirty Shirley
- Red Wine – South American Cabernet Sauvignon
Boneless Prime Rib Roast Recipe Tips
This boneless prime rib roast recipe is absolutely foolproof! It always ends up perfectly medium rare, juicy, and delicious. It’s great for big family holiday dinners but it’s also just right for an intimate, romantic dinner for two. The two best tips I can give are first, make sure you let the prime rib come to room temperature before you cook it. This means leaving it out for 2-4 hours depending on how big it is. The second is to use a meat thermometer to monitor the internal temperature. Remember, that when you take it out of the oven, it’ll keep cooking for a while so I like to remove it at 120 degrees fahrenheit (if going for medium rare which is 130-135 degrees fahrenheit). Loosely tent it with foil while letting it rest.
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Herb Crusted Boneless Prime Rib Roast
Ingredients
- 4 pounds boneless prime rib
- 2 tablespoons olive oil
- 1 tablespoon cracked black pepper
- 1 tablespoon salt , a bit more if you like it
- 1 tablespoon herbes de provence
- 2 teaspoons garlic powder
- 1 teaspoon onion powder
Instructions
Night Before Serving
- Rub the roast with the olive oil.
- Mix the pepper, salt, herbes de provence, garlic powder, and onion powder together and pat all over the roast covering as much surface as possible.
- Wrap tightly in plastic wrap and refrigerate.
When Ready to Cook
- Remove the roast from the refrigerator and unwrap.
- Let come to room temperature for 2-4 hours. This is critical for an evenly cooked roast.
- Preheat the oven to 450F.
- Place the prime rib on the roasting rack in the roasting pan, fat side up.
- Roast 15 minutes then turn the oven down to 325F and continue roasting about 1 1/2 hours.
- Remove roast from oven when meat thermometer registers 120F in the center if you are looking for medium rare which is 130-135F.
- Let stand for 15-20 minutes with aluminum foil loosely covering the roast to keep it warm. This lets the juices settle back into the meat. I cut it when it reaches about 120F-125F.
- Slice and serve.
Nutrition
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Click on the image to see the recipe. From left to right (all low carb): Low Carb Italian Beef, Low Carb Beef Stuffed Peppers, Low Carb Dr Pepper BBQ Sauce


This is the best boneless keto prime rib roast recipe on the internet. I love how easy the ingredients are and it tastes incredible. I’m not a big cook but with this, it’s just a matter of putting everything together – can’t go wrong with this recipe!
Hi- are you roasting this covered or uncovered?
uncovered. 🙂