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This slow roasted boneless prime rib recipe cooks low and slow until perfectly tender, pairing beautifully with warm au jus and a bright kick of horseradish.
Now, I know a recipe for slow roasted Boneless Prime Rib can be an intimidating meal to prepare for company. But trust me when I say this recipe is SO easy, I promise you that you can do it! So much of the prep work gets done beforehand. Then when your company arrives, your house smells amazing, and your prime rib has been slow-roasting for hours with the savory au jus simmering away on the stove, and let’s not forget the horseradish 🤤. There really is nothing more comforting than that!
Why You’ll Fall For This Boneless Prime Rib
This cut of meat is great because it feeds so many people. It is marbled with fat, so already tender and juicy. But then you salt brine and slow roast it for hours, which makes it even more tender and juice! Top the slow roasted prime rib with the au jus and horseradish – this meal will be one your friends and family will talk about for years to come! It’s perfect for Christmas, or even Thanksgiving (or Friendsgiving) if you’re not a turkey person! Great food and even better memories.
Table of Contents
Prep Your Ingredients: Prime Rib and Sauces
The Prime Rib
| Ribeye roast | Kosher salt | Black pepper | Avocado oil |
Salt brining is the most important step. Liberally season the roast with kosher salt and pepper, then refrigerate it uncovered for 12–24 hours. This tenderizes the meat, seasons it deeply, and helps it retain moisture. If you can, go the full 24 hours. If not, 12 hours is even worth it. Bring the roast to room temperature for 2–3 hours before cooking. This helps it cook evenly from edge to center.
The Searing Options
| Regular sear | Reverse sear | Roasting rack | Roasting pan |
You’ll choose between a regular sear (sear first, roast after) or a reverse sear (roast first, sear after). Both work beautifully, but I prefer the reverse sear for an evenly pink interior and a more controlled crust. Either way, the roast will cook at 250°F for 24–26 minutes per pound. Remember, the temperature continues to rise 5–10 degrees as it rests. The internal temperature list is in the notes of the recipe.
The Resting Time
| Cutting board | Sharp carving knife | 30 minutes |
After cooking, rest the roast for 30 minutes before slicing. This lets the juices redistribute so each slice is tender, rosy, and incredibly juicy. Do not skip the rest — it’s just as important as the cook.
The Au Jus
| Beef bones | Short ribs | Tomato paste | Shallots | Onion | White miso | Soy sauce | Red wine | Parsley | Peppercorns | Garlic | Celery | Carrot | Water |
Start the au jus at least 3 hours before serving. Rub the beef bones and short ribs with tomato paste and roast them at 400°F for 10–12 minutes to deepen their flavor. In a large heavy pot, caramelize the sliced shallots and onion in a little olive oil over medium-low heat for about 45 minutes, stirring often. Add the roasted bones, miso, soy sauce, red wine, parsley, peppercorns, garlic, celery, carrot, and 8 cups of water. Let it simmer gently for 2–4 hours while the prime rib cooks, adding water as needed to keep everything submerged. Strain before serving.
The Horseradish
| Creamy Horseradish | Fresh Prepared Horseradish |
Mix the ingredients for either the creamy horseradish or the freshly grated version. Store in an airtight container in the fridge. This can be done days ahead, and I love serving it in small ramekins alongside the prime rib.
Substitutions and Variations
Ingredient Swaps
- If you like your boneless prime rib with gravy over au jus and horseradish, you can always use the drippings mixed with flour and beef broth to make an excellent gravy.
- You can use an alcohol-free red wine or just use beef broth for the au jus if preferred.
Flavor Twist: Similar Slow Roasted Recipes
- Slow Roasted Beef Tenderloin (Chateaubriand): A whole slow roasted tenderloin with a side of béarnaise sauce.
- Slow Roasted Miso Glaze Short Ribs: This Asian-inspired miso maple boneless short ribs recipe combines miso, gochujang, and maple glaze for tender, fall-apart short ribs with rich umami flavor.
- Braised Beef Short Ribs: Braised beef short ribs cooked in red wine with miso, tomato paste, aromatics, and ancho chile, served meltingly tender over creamy polenta.
The Perfect Pairings
Start your night off with a milky dirty martini and then move into the next course, your incredible boneless prime rib recipe and pair it with a creamy potato puree and a fresh butter lettuce salad. End your night with a passion fruit panna cotta.
Boneless Prime Rib: Questions Answered
A good rule of thumb for Prime Rib is to have about 1 lb per person.
For medium-rare (my recommended doneness), roast the prime rib at 250°F for 24–26 minutes per pound, then let it rest for 30 minutes. Because ovens vary, using a meat thermometer is essential for perfect results.
Doneness Guide:
Rare: 120–125°F – bright red center fading to pink toward the edges
Medium-rare: 130–135°F – warm pink center with a slightly red middle
Medium: 135–140°F – evenly pink/mauve throughout
Well-done: 145°F and above – little to no pink, mostly brown
This can be personal preference but most people, including myself, think thin slices are better! The sauce distribution is better and the meat is extra tender when sliced thin!
I like to have the thermometer in the oven while cooking so I can monitor it so using an oven-safe one is the way to go for this. You can use the ThermoPro Digital Cooking Thermometer or for a wireless option that you check on your phone you can get this Wireless Meat Thermometer.
Sure! This horseradish pairs so well with the Prime Rib and you can actually keep the prepared it in a sealed container for up to three months.
Yes, can use an alcohol-free red wine or just use beef broth instead.
Chef Nadia’s Tip
- Salt brining is essential for a tender, flavorful roast. It seasons the meat all the way through and helps it retain moisture. A full 24-hour salt brine gives the best results, but even 12 hours is worth it if you’re short on time.
- Let the roast sit at room temperature for about 2 hours before cooking. Starting with an even internal temperature ensures the prime rib cooks gently and evenly.
- Always rest your prime rib for 20–30 minutes before slicing. This lets the juices settle so every slice is tender and juicy.
- For the most accuracy, use a meat thermometer rather than relying only on timing. See the notes in my recipe for internal temperature guide.
Slow Roasted Prime Rib with Au Jus & Horseradish
Equipment
- 1 Roasting Pan with rack
- tongs
- 1 Skillet, if searing on the stovetop
- baking sheet with aluminum foil
- 1 large heavy bottom pot, for au jus
- strainer
- Bowl
Ingredients
Prime Rib
- 8-10 lb ribeye roast
- kosher salt, ½ teaspoon per pound
- black pepper, to taste
- avocado oil, for searing
Au Jus
- 4 beef bones
- 4 short ribs
- 4 oz tomato paste
- 1 tbsp olive oil
- 2 shallots, sliced
- 1 large onion, sliced
- 1 ½ tbsp white miso paste
- 2 tbsp soy sauce
- 1 ½ cup red wine
- 1 bunch parsley, whole
- 2 tbsp peppercorns
- 1 garlic head, whole
- 2 celery ribs
- 1 large carrot
- 8 cups water, + more as needed
Creamy Horseradish
- ¾ cup sour cream
- 3 tbsp prepared horseradish
- ½ tsp worcestshire sauce
- ½ tsp red wine vinegar
- 3 tbsp mayo
Prepared Horseradish
- 1 horseradish root, about 4-6 inches, grated
- 2 tbsp red wine vinegar
- 3-4 tbsp water
- ¼ tsp salt
Instructions
Salt Brine (day before):
- Liberally season the roast with kosher salt and black pepper, then refrigerate it uncovered for 12–24 hours. Before roasting, bring it to room temperature for 2–3 hours.8-10 lb ribeye roast, kosher salt, black pepper
Au Jus (start 3–4 hours before serving):
- Preheat your oven to 400°F. Rub the beef bones and short ribs with tomato paste and place them on a foil-lined baking sheet. Roast for 10–12 minutes.4 beef bones, 4 short ribs, 4 oz tomato paste
- Meanwhile, heat the oil in a large heavy-bottom pot. Add the sliced shallots and onions and let them slowly caramelize for about 45 minutes, stirring frequently.1 tbsp olive oil, 2 shallots, 1 large onion
- Once the onions and shallots are caramelized, add the roasted bones, short ribs, white miso paste, soy sauce, red wine, parsley, peppercorns, garlic head, celery ribs, carrot, and 8 cups of water. Let the mixture simmer gently for 2–4 hours, adding more water as needed to keep everything submerged. Strain and keep warm.4 beef bones, 4 short ribs, 1 ½ tbsp white miso paste, 2 tbsp soy sauce, 1 ½ cup red wine, 1 bunch parsley, 2 tbsp peppercorns, 1 garlic head, 2 celery ribs, 1 large carrot, 8 cups water
Creamy Horseradish
- Combine the ingredients. Store in an airtight container in the fridge. This can be made several days in advance.¾ cup sour cream, 3 tbsp prepared horseradish, ½ tsp worcestshire sauce, ½ tsp red wine vinegar, 3 tbsp mayo
Prepared Horseradish
- Combine the ingredients. Store in an airtight container in the fridge. This can be made several days in advance.1 horseradish root, 2 tbsp red wine vinegar, 3-4 tbsp water, ¼ tsp salt
Prime Rib – Regular Sear:
- Preheat your oven to 250°F and position a rack in the center. Heat a large pan over high for 2–3 minutes, then lower the heat to medium-high. Add avocado oil and sear the roast on all sides until well browned, about 10–15 minutes.avocado oil
- Transfer the roast to a roasting rack inside a roasting pan. Roast at 250°F for 24–26 minutes per pound, until the internal temperature reaches 130–135°F for perfect medium-rare (I pull mine at 120°F since it rises while resting). Let it rest for 30 minutes before slicing.
- Prime Rib – Reverse Sear:
- Preheat your oven to 250°F and position a rack in the center. Place the room-temperature roast on a roasting rack inside a roasting pan. Roast at 250°F for 24–26 minutes per pound, pulling it at 120°F for medium-rare. Let it rest for 30 minutes.
- After resting, you can either:– Increase the oven to 475–500°F and return the roast for 6–10 minutes until a golden crust forms, or– Sear it in a hot pan with avocado oil until browned on all sides (about 10–15 minutes).
Notes
- Rare: 120–125°F – bright red center fading to pink toward the edges
- Medium-rare: 130–135°F – warm pink center with a slightly red middle
- Medium: 135–140°F – evenly pink/mauve throughout
- Well-done: 145°F and above – little to no pink, mostly brown
Nutrition
Nutrition information is automatically calculated, so should only be used as an approximation.
On the Au Ju section you describe how to roast the bones etc and then how to caramelize the onions and shallots but you don’t specify when to combine the two. I’m guessing it’s when everything is added to the pot to simmer but it doesn’t say.
Hey Jennifer, Thank you so much for telling me that! I updated the entire recipe and fixed that!