A beef tenderloin roast is one of the most delicious, expensive and luxurious cuts of beef you can put on your table. It comes from the short loin portion of the steer and is tender enough to cut with a fork. A beef tenderloin roast is a fine choice for a celebratory meal.
A beef tenderloin is the long muscle that runs along the spine of a steer. A part of the short loin section of the cow, the tenderloin attaches to the backbone at one end and to the pelvis at the other. Since this muscle doesn't get much use, a beef tenderloin is one of the most tender cuts of beef. It also is one of the most expensive---this muscle also is the source of fillet mignon.
Trimmed or Untrimmed?
You can buy beef tenderloins either trimmed or untrimmed. A whole untrimmed beef tenderloin weighs between 2.72 and 3.63 Kilogram and will cost between $70 and $130, depending on the vendor. Once it's trimmed into a roast, it will weigh about 5 to 6 pounds. A ready-trimmed roast will cost a little more per pound than an untrimmed version. A home cook can trim up a tenderloin very quickly and end up with a beautiful, uniformly sized roast that will feed between 10 and 12 people with sterling results and absolutely no waste. All that you have to take off a tenderloin to get it ready for roasting is a little connective tissue, some fat and a bunch of small pieces of meat that isn't part of a roast. Set those bits aside to make sautés or beef stroganoff later. Be sure to slice off the silverskin, a thin, whitish membrane that covers the outside of the muscle.
Preparing the Roast
While a beef tenderloin roast is very tender, it also is rather less flavourful than other cuts of beef, so the roast will benefit from a dry or wet rub. You can also marinate it briefly, though you don't want to soak it too long because the meat is so soft that overexposure to acidic liquid can render it mushy. Whether you choose a marinade or a dry rub, you should take the roast out of the refrigerator about an hour before you plan to cook it. Dry it thoroughly with paper towels, and then rub it lightly with a mixture of your favourite fresh or dried herbs, garlic and a little oil---vegetable or olive, according to your preference. Salt and pepper it generously.
At this point, you can sear the tenderloin in a skillet to give the exterior a head start before roasting it, or simply put it on a rack in a roasting pan and slide it into a preheated 425 degree oven. Immediately turn the heat down to 350. A beef tenderloin roast will cook in 45 minutes to an hour, so after 30 minutes, test the internal temperature with a meat thermometer. For rare meat, the temperature should register 120 degrees; for medium, it should be 140.
When you take the meat out of the oven, set it aside in its pan and let it rest for about 15 minutes. During this rest, the juices will retreat from the outside of the meat to the inside, and the internal temperature will rise by another 5 degrees or so. If you cut the meat as soon as it comes out of the oven, the juices will run out and the meat will be dry and chewy. After it rests, you can carve the roast into thick or thin slices. You can also serve beef tenderloin roast lukewarm or even cool.