How long do you cook a 6 lb prime rib

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Nothing is better than a perfectly cooked prime rib roast. That buttery perfection that just melts in your mouth,  slices with the barest pressure of a knife, covered in a brown gravy, with a side of mashed potatoes and greens of some sort…culinary heaven.

How to Cook Prime Rib Roast from Start to Finish!

This fool proof method will guarantee you the juiciest, best prime rib roast you’ve ever had! Since I became emboldened by the fact that I own a meat thermometer, and prime rib roasts are affordable this time of year (not so many tears when I screw it up) I have roasted about 5 over the past year, and just did another one for Thanksgiving lunch this Saturday. Yes, a lunch. I worked all weekend evenings this long weekend, so my parents were kind enough to make a turkey feast for the kids and Mike, while I had hospital cafeteria food. So I think a prime rib lunch before one of my shifts was entirely deserved 😉

Ingredients Needed for Cooking Prime Rib

• prime rib roast
• butter

How to Cook a Prime Rib Roast – Instructions

• Remove your roast from all its packaging and  let it sit out for an hour until it’s about room temperature. Never, ever, cook a roast from frozen. The outside will be overdone and the inside will be raw. Absolutely a mess.
• Take the butter and cover not only the ends, but if you don’t have a layer of fat on the top, cover that as well. When choosing prime rib, you actually want a layer of fat on the top. This helps make the roast oh-so tender. This roast didn’t have a layer, it was butchered too close,  so I put a layer of butter on top.
• Preheat your oven to 450 degrees at this point.
• Once it’s covered, place on a wire rack in a pan deep enough to catch the drippings.
• Now we want to sear the roast. Place it in the 450 degree oven for about 20 minutes.
• It should be nicely browned (seared) on the outside now. This in theory seals in all the juices, and to be honest, when I do it this way I hardly have any drippings for gravy. So it really must do something to hold in the juices. Now you can turn the oven down to 325 degrees and roast.
• You cannot cook prime rib without a meat thermometer. You can’t. This masterpiece depends on a precise temperature, with it being pulled out of the oven at the exact right moment. This can’t be achieved without a thermometer. And to be honest, if you spend $50 on a roast, why on earth wouldn’t you pick up a $15 digital thermometer?
• I measure on the outside where on the thermometer it will hit and put my fingers there.
• Then keeping my fingers on the same spot, I put the thermometer in the middle of the roast until it reaches to where I measured. Make sense? Probably not. I usually just pretend I know what I am talking about.
• Now place in the 325 degree oven for baking. Below are guidelines for roasting a prime rib roast.  You want to pull the roast out a minimum of 10 degrees BEFORE you hit these temperatures. Once the roast is out, tent it with foil, and let it sit for about 20 minutes. The temperature will rise at least another 10 degrees if you cover it in foil. It also lets the juices set and flow back to the meat. Be sure that you always cook your food to their safe temperature.

Prime Rib Roasting Internal Temperatures

• Blue in the middle– 110 degrees Fahrenheit  – when the middle of the roast still “quivers”
• Rare- 120-125 degrees Fahrenheit in the middle
• Medium-rare– 125- 135 degrees Fahrenheit in the middle
• Medium – 135- 140 degrees Fahrenheit in the middle. You usually don’t want it cooked this much as you lose the tenderness that prime rib is known for.
• Medium Well-140- 150 degrees Fahrenheit
• Well-done– 155 + degrees Fahrenheit

So, you have pulled it out 10 degrees Fahrenheit before it’s ready and tented it in foil for 20 minutes, right? Now it’s time to remove the bones. You want to slice along the curve of the bones.

How long do you cook a prime rib roast per pound?

I would allow 15 minutes per pound for cooking time on your prime rib, but always give yourself some wiggle room when it comes to time and serving your holiday meal.

Now, this post on how to cook a prime rib roast sure brought out the well done lovers in the crowd. Listen : I’m just passing on what all the experts say is the best for this cut of beef. And yes, they are experts. Trained for years at culinary school, taught how to work with meat and how to cook it best.

You can definitely cook this until it’s well done, but don’t think that I’m going to take the fall for you possibly ruining a $100 roast! This method works incredibly well with prime rib roasts and it’s how I do it every year. However I can’t take responsibility for when you change a recipe!

Try my Leftover Prime Rib Hash Skillet with your leftovers, it’s amazing!  If you need another roast recipe there is also my How To Cook a Sirloin Roast.

IF YOU ARE LOOKING FOR A FLAVOURED PRIME RIB ROAST TRY MY HERB AND GARLIC PRIME RIB ROAST RECIPE!.That is a super flavourful roast and is shown in the video below! Happy cooking everyone, I hope your prime ribs turn out amazing!

Karlynn

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Learn to cook like the Kitchen Magpie

• ▢ one prime rib roast of choice
• ▢ butter if there isn't enough fat

• Remove your roast from all its packaging and  let it sit out for an hour until it's about room temperature.

• Take the butter and cover not only the ends, but if you don't have a layer of fat on the top, cover that as well. This roast didn't have a layer, it was butchered too close,  so I put a layer of butter on top.

• Preheat your oven to 450 degrees at this point.

• Once it's covered, place on a wire rack in a pan deep enough to catch the drippings.

• Now we want to sear the roast. Place it in the 450 degree oven for about 20 minutes.

• Turn down the oven to 325 degree and cook some more. Below are guidelines for roasting a prime rib roast .You want to pull the roast out a minimum of 10 degrees BEFORE you hit these temperatures.

• Once the roast is out, tent it with foil, and let it sit for about 20 minutes. The temperature will rise at least another 10 degrees if you cover it in foil. It also lets the juices set and flow back to the meat.

• Now it's time to remove the bones. You want to slice along the curve of the bones and remove the meat. Slice it off, then slice as you would normally slice a roast.

• Serve and enjoy!

Prime Rib Roasting Internal Temperatures

• Blue in the middle- 110 degrees - when the middle of the roast still "quivers"
  

• Rare- 120-125 degrees in the middle

• Medium-rare- 125- 135 degrees in the middle

• Medium - 135- 140 degrees in the middle. You don't want it cooked this much.

• Medium Well-140- 150

• Well-done- 155 +

• Cook to the temperature you desire. See post for instructions.
• The time on this is for a 15 lb prime rib roast, adjust your cooking time appropriately.
• NUTRITIONAL VALUES WILL VARY ROAST TO ROAST, do not use these as accurate values. 

Calories: 1352kcal, Protein: 61g, Fat: 120g, Saturated Fat: 50g, Cholesterol: 274mg, Sodium: 201mg, Potassium: 1002mg, Calcium: 34mg, Iron: 6.5mg

All calories and info are based on a third party calculator and are only an estimate. Actual nutritional info will vary with brands used, your measuring methods, portion sizes and more.

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