When I was catering, sliced Beef Tenderloin was my go-to.  I served it with soft rolls for "heavy hors d'oeuvres," on bite-sized toasts for an elegant passed hors d'oeuvres or thickly sliced with blue cheese sauce (also based on one of the Barefoot Contessa's recipes) as an entree.
My method for preparation was always the same, per the Barefoot Contessa's book, Parties, 500 degree oven for 30-35 minutes, rest 15 minutes, then slice.  Fabulous every time.  Well, almost every time.  On occasion, I would run into an oven that was too hot or a guest that would chat with me a couple minutes too long, only to discover the beautiful beef tenderloin went from perfectly "rare" to "medium" in a matter of two minutes.  When cooking it at that super high temp, just as when grilling, you must time the cooking perfectly to avoid overcooking - or under-cooking.

I read Ina's new recipe for Slow-Roasted Filet of Beef (beef tenderloin) on our drive to my sisters last year on Christmas Day, knowing that I was in charge of cooking the beef tenderloin for dinner that night.  Ina had changed her tune from fast and hot to slow and low with apparently fabulous results.  Hum... it was a big risk.  Not only was it Christmas and everyone was looking forward to feasting on the traditional beef tenderloin, but I wasn't the one who had paid for it.  When you're trusted with a piece of meat for which someone else forked over $100+, you better know what you're doing!

I spent the 3 hour drive researching the slow and low method for beef tenderloin.  After reading several other reviews and recipes that claimed the same as Mrs. Garten, I asked Mike what he thought I should do?

He said, "What's the name of the book?"


I put our Christmas Dinner fate in the capable hands of The Barefoot (...even though, I could hear her saying the back of my head, "Never try a new recipe when you're entertaining - only tried and true recipes that you know will work every time.").

Our Christmas Dinner was a huge success - everyone "oohhing and aahhhing" over the perfectly rare, perfectly tender - almost silky - beef tenderloin.  I shouldn't have doubted her for one minute.

When winter weather interrupted last year's New Years Eve plans, Mike and I opted to stay in for a night of indulgence.  Beef Tenderloin for two.  

This is what the beef tenderloin section looks like at my grocery store during the holidays.  You can also find them at Costco.  Typically, tenderloins are 5-6 pounds each, making them perfect for a crowd of 10-14 people, generously.  I called our butcher and asked for them to cut a 2 pound section for me. 

Most butchers are happy to do this because they just cut the rest of the tenderloin into filet steaks to sell.  I also had them trim (the fat) and tie it, as you can see above.

Slow-Roasted Beef Tenderloin

5-6 pound Beef Tenderloin, trimmed of fat, tied
olive oil
Sea Salt
Fresh Cracked Pepper

Trim the fat from the beef, then tie it in sections with cotton twine.  Drizzle with olive oil, then coat in salt and pepper.  Place on a baking sheet.
*For preparation in advance, trim fat, tie and place on a baking sheet. Wait until just before roasting to season.

Roast at 275 degrees for 1 hour to 1:20 minutes until the inside of the beef reaches 130-135 degrees.  Remove from oven and let rest for 10 minutes.  Slice 1-inch thick slices.

Photo : Here is the beef baking at 275 degrees after a generous salt and pepper.

I covered it with foil to let it rest.

Ready for carving at approx. 10pm on New Years Eve!

One more closeup... 

Perfectly rare all the way through.  When cooking it at the low temperature vs. high, I found that it cooks more evenly.  Instead of more "medium-well" ends and "rare" center, then entire tenderloin was hot pink and juicy, similar to a prime rib roast.  I highly, highly recommend this method.

See the entire Holiday Dinner Party Menu and print the detailed cooking schedule, here.