Pork is a favorite among the world's carnivores, except where it's shunned for cultural or religious reasons. Pork tenderloins, or fillets, are an especially choice cut. Just the right size to be roasted as a meal for two or four people, they're also the leanest of pork cuts: at less than 3 grams of fat per 3-ounce portion, they're comparable to a skinless chicken breast. That makes them an especially healthful choice when grilled or roasted.
About the Fillet
One of the rules of meat is that the more a given muscle is used, the tougher it becomes. The fillets are a pair of muscles that aren't worked and are correspondingly tender. They're located toward the back of the hog in its loin section. The main loin muscles run along the top of the animal's spine and chine bones, while the tenderloins are attached to the underside. They're roughly cylindrical in shape, with tapered ends. An average fillet is roughly 2 1/2 to 3 inches in diameter and 12 to 15 inches long, and it weighs approximately 2 pounds.
Preparing the Fillet
Although the fillet commands a premium price, it's reasonably economical because there's very little wastage. There are no bones and minimal fat to be trimmed away. Begin by pulling off any pieces of surface fat you can find or trimming them with the tip of a sharp knife. Near the end of the fillet is a sheet of tough, off-white connective tissue, referred to as "silverskin." It doesn't soften when cooked, so trim it away by sliding the tip of your knife underneath, then slicing it away. Angle your knife blade so it presses against the silverskin, to minimize waste.
Seasoning and Searing
Like any other piece of pork, the fillet plays nicely with most seasonings. You can be minimalist and use just salt and pepper, or opt for a more adventurous mixture of flavors such as a thin layer of Dijon mustard mixed with small amounts of garlic paste and finely chopped fresh rosemary. The roast will taste best if the outer surfaces are well browned, so many cooks opt to sear it first on the stovetop. Heat a heavy skillet to medium-hot, then pour in a tablespoon of oil. Sear the fillet on all sides, either in one piece or equal halves.
If you've opted to sear the fillet first, preheat the oven to 425 degrees Fahrenheit and simply transfer the hot skillet to the oven rack to finish cooking. If you haven't seared the fillet, preheat the oven to 450 F and use a sheet pan or a small roaster. Cook a seared fillet for approximately 15 minutes, until its internal temperature is 145 F when tested with an instant-read thermometer. Unseared fillets will require approximately 5 minutes longer. Let them rest, loosely covered with foil, for 5 minutes before servings. A full fillet will serve four people, while a half will serve two.