Cooking a large beef tenderloin is almost as simple as cooking a smaller roast and allows you to feed a large number of people with relatively little effort. Because the tenderloin is taken from a little-exercised area of the animal, it is the tenderest cut of all, making it a good choice for holidays or special occasions. Simple cooking methods are best; elaborate sauces and rubs obscure the natural, mild flavor of the beef. Remove the roast from the refrigerator about 1 hour ahead of time. The meat will cook more evenly if it is started at room temperature.
Roasting a Crispy Outer Crust
Pat the tenderloin dry with a paper towel, then season all sides of the meat lightly with salt.
Place a small amount of vegetable or olive oil in a large, heavy skillet. Heat the oil over medium heat, then place the tenderloin in the pan and sear the meat, undisturbed, until the bottom of the meat is brown. Turn the meat and cook, turning as needed, until the meat is evenly brown on all sides.
Transfer the tenderloin to a large roasting pan with a rack. Use a sturdy pan with two handles because the roast will be heavy. Be sure the tenderloin isn't crowded in the pan because even cooking requires air circulation around all sides of the meat.
Sprinkle the meat lightly with freshly ground black pepper and your desired dried seasonings.
Place the roasting pan in an oven preheated to 450 degrees Fahrenheit. Roast the tenderloin until a meat thermometer inserted into the center of the meat registers 135 F for a medium-rare roast or 150 F for a medium roast.
Rotate the pan once, about halfway through the cooking time. Allow a total cooking time of approximately 20 minutes per pound -- approximately 2 1/2 to 3 1/2 hours for an 8- to 10-pound tenderloin.
Transfer the tenderloin to a carving board, with the meat thermometer in the meat. Allow the meat to rest for 15 to 20 minutes before carving, or until the temperature peaks and begins to drop.
Carve the tenderloin into uniform slices. Place the slices on a large platter and serve.
Fork-Tender Braised Tenderloin
Heat a small amount of oil in a Dutch oven or a heavy skillet. Place the tenderloin in the hot oil and sear the meat, turning often, until it is brown on all sides.
Season the meat with salt and pepper, or your choice of dried seasonings. Pour in about 1 1/2 to 2 cups of water or broth.
Cover the pan tightly. Bring the liquid to a boil.
Lower the heat and let the liquid simmer gently for approximately 2 1/2 to 3 hours, or until a meat thermometer registers 135 F for a medium-rare roast.
Remove the tenderloin from the oven. Allow the meat to rest for 15 to 20 minutes before serving.
Smoky Grilled Roast
Turn the barbecue grill on medium-high, or 400 F. To test the heat of a charcoal grill, hold your hand about 4 inches above the grill. You should be able to hold your hand in that position for 4 to 5 seconds.
Sprinkle the tenderloin with salt and pepper and the dry seasonings of your choice. Press the seasonings into the meat, then let the tenderloin rest for about 1/2 to 1 hour.
Oil the grate lightly to prevent sticking.
Grill the tenderloin, turning often, until the meat is evenly brown on all sides. Use a meat thermometer to ensure the tenderloin registers at least 135 F in the center of the meat.
Transfer the tenderloin to a serving plate. Allow the meat to rest 15 to 20 minutes, then carve and serve.