GRILL-ROASTED BEEF TENDERLOIN

BECAUSE THE TENDERLOIN SITS UP JUST UNDER the spine of the cow, it gets no exercise at all and is therefore the most tender piece of meat on the animal. It is one of the two muscles on either side of the bone in the ultra-premium steak known as the porterhouse, so when it is removed from the cow as a whole muscle, it sells for an ultra-premium price.

A whole beef tenderloin can be purchased "unpeeled," with an incredibly thick layer of exterior fat left attached, but it's usually sold "peeled," or stripped of its fat. Because of our many bad experiences with overly lean meat, we purchased several unpeeled roasts. However, it quickly became clear that there was too much fat to leave on the roast. We found that the fat prevented the formation of a thick brown crust, one of the hallmarks of a perfectly cooked tenderloin.

We then tried peeling the roasts in the test kitchen. In the end we removed three pounds of waste from an eight-pound unpeeled roast, which had cost us $56. Since we could buy a five-pound peeled roast for just $40, the unpeeled roast was actually more expensive per pound of edible meat and required a lot more effort. In fact, we found it best to leave the peeled roast alone, letting the scattered patches of fat on the exterior flavor the meat as it cooked.

Grill-roasting a whole tenderloin poses a challenge because of its shape (see figure 32). This cut is thick at one end and tapered at the other, which makes for uneven cooking. The solution to this problem was to fold under the tip end of the roast. We found that tying the roast bulks up the tenderloin center so it is almost as thick as the more substantial butt tender. Tying the roast also ensures even cooking.

As for the actual cooking process, we found that a beef tenderloin cooks perfectly over indirect heat in 35 to 40 minutes. To build a nice thick crust on the meat, the initial charcoal fire should be fairly hot—about 375 degrees is ideal. We tried turning the roast but found that opening the lid caused the fire to lose heat and that the roast was browning evenly anyway.

Once the roast is cooked to 125 degrees (the optimum temperature if you like your meat cooked medium-rare), it should be pulled off the grill and allowed to rest; the internal temperature will rise by at least 5 degrees. Most roasts can be carved after 15 minutes, but we found that beef tenderloin improves dramatically if left uncarved even longer. If cut too soon, the slices are soft and flabby. A slightly longer rest, however, allows the meat to firm up into a more appealing texture.