How Long To Cook Prime Rib At 400 Degrees

If you have ever wanted to know how to cook prime rib, you can find out right here. Our family has been making this for years, and there are many ways to make this holiday classic. This is one of our most requested Christmas dinner recipes.

Whether you like your beef rare, or well done, we will show you how to make it just the way you like it!

A boneless prime rib of beef roasted to medium-rare, in a roaster.

Jump to:

How to roast it
What you need to make this
The different grades or cuts
Bone-in or boneless
How to season this
Two ways to roast it
How to use the leftovers
Realted recipes:
📖 Recipe
Comments

How to roast it

This is a meat lover's post. If eating meat offends you, then please, skip this one.

If however, you or someone close to you enjoys a sublime cut of beef now and then, this is a post you will want to take a closer look at.

A finished beef roast sitting in a roaster on top of celery and potatoes.

What you need to make this

Standing Rib Roast
Garlic
Salt
Pepper
Butter

The different grades or cuts

When you look for a one of these to buy, you may see that there are two grades to choose from.

Prime Grade
- "Prime" is the highest grade and the most expensive, about 25% higher in price than the choice grade.
- The prime grade of this cut of beef is heavily marbled with streaks of fat to make it more tender and flavorful.
Choice Grade
- "Choice" grade of prime rib is the second-highest rating and indicates beef that has less marbling.
- This is the type most often served in restaurants.

An uncooked hunk of beef, covered with garlic, salt, and pepper.

Bone-in or boneless

When making your selection, besides choosing how to season it, you also have the option of "bone-in" or boneless. I don't believe there is any difference in the flavor between the two.

Bone-in
- Bone-in prime rib can be more challenging to slice.
- Figure on a pound per person with a bone-in roast.
Boneless
- Easier to cut for serving.
- Figure on about ½ pound for each person.

If you choose bone-in, the roast should be placed in the roaster, with bone on the bottom.

A seasoned, uncooked beef roast sitting in a roaster with carrots and celery. — Allow your meat to get to room temperature before placing it in the oven

Start at Room Temperature

Take the meat out of the refrigerator a couple of hours before you place it in the oven. Allowing it to reach room temperature before roasting helps ensure that it roasts evenly throughout.

How to season this

For the best prime rib, all you need to season it with is garlic, salt, and pepper.

Garlic
- Chop or mince the garlic and then use your hands to apply an even coat around the meat.
Salt
- Apply a generous layer of salt around the entire roast.
- I prefer to use kosher salt for it's larger crystals.
Pepper
- Sprinkle a generous layer of fresh ground black pepper around the entire beef roast.

Allow the seasoning to flavor the meat for an hour or two while it sits on your counter-top.

The Fat Cap

A standing rib roast will have a fat cap that insulates the meat while it cooks and adds some nice flavor under high heat.

Score the fat pad (without cutting into the meat), to allow some of the seasoning to penetrate the meat for added flavor and rendering.

An uncooked piece of meat rubbed in butter with a temperature probe stuck in it.

Using Garlic Butter as a Seasoning

In the above photo, I compounded about a half-pound of butter along with a head of minced garlic. I rubbed this garlic butter compound all over the meat and then added the kosher salt and pepper.

In addition to the extra flavor, the butter provides a nice crispy finish to the exterior surface of the meat.

Two ways to roast it

I use two methods of making a standing rib roast; both give me the same excellent results.

One method is temperature-based; the other is all about time. Both methods have a couple of things in common:

Both start with a high oven temperature, which is lowered.
Both use "carryover cooking, which is when the meat continues to cook after it is removed from the oven.

Let's take a look at both of these methods.

Temperature-Based Method of Making This

Remove the roast from the refrigerator a few hours before placing it in the oven to allow it to come to room temperature.
Season all sides of the beef as shown above.
Preheat oven to 400° F.
Place in oven.
Reduce heat to 300°
Keep prime rib in the oven until it is 5-7°F less than this temperature guide below.
Remove from oven and tent loosely with foil, for 15 minutes to allow for carryover cooking.

These are final doneness temperatures. Your "pull from the oven" temperature should be 5-7°F (3-4°C) below the temperatures shown (depending upon the size of the prime rib roast) to allow for carryover cooking.

Time-Based Method

This method is a bit simpler as there is not temperature measuring involved.

Same as step one above.
Same as step two above.
Same as step three above.
Reduce heat to 375° when you put your roast in the oven.
After one hour, turn the oven off (do not open door).
An hour before you want to eat, turn the oven back on to 375°.
Roast for an hour at 375° and then remove from oven, tent the meat loosely with foil and allow to rest for 15 minutes before carving.

For Both Methods:

Place rib on a few stalks of celery or some potato wedges (slathered with olive oil or melted butter.

The celery will give the au jus some nice flavor, and the potatoes are a great one-and-done side dish!

If you want to treat yourself to something special and delicious, consider learning how to roast prime rib.

Although you can season an oven-roasted prime rib with anything, I use just three or four ingredients in my seasoning:

Fresh garlic
Kosher salt
Fresh ground pepper
Sometimes butter

How to use the leftovers

Prime Rib Phyllo Pot Pie
- Savory and simple comfort food that is the perfect home for any leftovers.

Leftover Prime Rib Enchiladas
- A versatile and delicious leftover recipe the whole family loves.

Leftover Beef Tacos
- This easy recipe for tacos and versatile and can be made with leftover beef, chicken, or pork.

Give this recipe a try; chances are if it is your first time this luxurious meal, it will not be your last.

A plate of medium-rare prime rib with asparagus and carrots.

Realted recipes:

Braised Beef
How to Debone and Roll a Standing Rib Roast

This post is dedicated to my sister Ann, who we lost far too early. One of the funniest and smartest people I have ever known, I miss you every day and will always be thankful for the love, the laughter, and the incredible food you fed me and the many lessons on how to roast prime rib.

Dan from Platter Talk standing in the kitchen. — Dan

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📖 Recipe

Slices of prime rib, medium-rare, in a roaster.

▢ 7 lbs Prime Rib
▢ 5 cloves crushed fresh garlic
▢ Kosher salt quantity dependent upon size of prime rib
▢ Fresh ground pepper corn
▢ 3-4 celery stalks for bed of roaster optional

Apply non-stick treatment to bottom or roaster
Lay celery on bottom of roaster
Rub fresh garlic throughout surface of the roast.
Apply a generous amount of kosher salt to outside of the meat, covering all sides.
Next, evenly distribute fresh ground peppercorn.
Place meat in roaster or baking dish, bone side down, if bone-in.
Allow prime rib to set out at room temperature 2-3 hours prior to placing in oven
Preheat oven to 400 degrees F.
Place (room temperature) roast in oven for 20 minutes, uncovered.
After 20 minutes, reduce heat to 300 degrees F.
Roast until internal temperature of meat is 120 to 125 degrees F.
Remove from oven, loosely tent with foil and allow to rest 30 minutes on counter top. This allows for "carry-over" cooking where the rib will continue to cook after removal from oven.
While carry-over cooking is occurring, into medium size saute pan, drain all the juice from the roaster except for two tablespoons.
Over medium low heat, warm the juice and stir in 1 tablespoon flour. Salt and pepper to taste and stir. The au jus will be thin and should remain so as it is not gravy but rather a supplementary condiment to provide flavor, juice, and warmth.

Wondering what size prime rib to use? Figure on 8 to 12 oz. per serving. This generally allows for plenty plus a little left over.
Use very generous amount of kosher salt when initially seasoning meat.
Roaster should not be over sized relative to size of prime rib. Optimally, it should just fit, without touching sides of container.
The above method and temperature should give you a cut of medium-rare. With this roast, it is always best to err on the side of rare. If the cuts are too rare for guests, the meat can quickly be finished off in a saute pan, stove top. This is usually possible in a very short period of time, a minute or less over medium high heat.
Allowing the roast to set, loosely tented with foil, is vital for attaining the correct level rareness. Equally important, it allows the juices of the rib to be reabsorbed into the meat, resulting in a succulent and juicy serving of beef.
Finally, do not open the oven door while the roast is cooking, unless you need to check the temperature.