Beef tenderloin is the most expensive cut of meat on the steer. At a good butcher or supermarket, a trimmed center-cut tenderloin can run you as much as $25 to $30 per pound! But there are ways to minimize that cost. The best way is to buy the tenderloin whole and untrimmed, bring it home, and trim it yourself.
At my local Whole Foods, this shaves a full $10 per pound off of the trimmed cost, which translates to about $5 per pound savings after trimming away and discarding the scrap. At stores like Costco or other big box supermarkets, you can find untrimmed tenderloin for as little as $6 a pound.
Trimming yourself takes two things: a good, sharp, flexible boning knife, and a bit of practice. Here's how you do it.
Removing the Chain
When you've got the tenderloin on the table, you'll notice that there's a tapered end and a fat end. Along the length of it, you'll also find a narrow strip of meat that is only loosely attached to the main bit. This is known as the "chain," and should be removed for roasting. Grab the end of it closest to the tapered side of the tenderloin, then pull it away from the rest of the meat. It should come off very easily, requiring only a little snip with the tip of your knife at the end to remove it completely.
The meat from this chain can be salvaged by carefully trimming away any extra fat or connective tissue. It's great in stir-fries or quick stews.
Removing the Connective Tissue
Now it's time to remove the thick layer of connective tissue that wraps the tenderloin. Start by sliding the tip of your knife underneath the layer of white connective tissue somewhere around the middle of the roast (the exact position doesn't matter). Try to keep the knife tip as close to the surface of the meat as possible in order to minimize the amount of actual meat you cut off.
Slide the Blade Through
Once the tip of the blade has exited the other side of the connective tissue, slide the blade underneath the tissue to cut it free from the meat, using your free hand to pull the connective tissue taught against the blade. Your blade should be angled slightly away from the meat so that you are scraping it up against the connective tissue. This will also help minimize meat loss. Keep sliding until the blade exits a few inches away from where you started.
Slide Knife in Reverse
Now turn your knife over, grab the end of the flap you just created with your free hand, pulling it taught, and slide the knife back underneath, this time going in the opposite direction. The flap of connective tissue should come off in one solid piece.
Repeat this process until all connective tissue is removed.
Trim Off Excess Fat
Once the connective tissue is removed, trim away the small pockets of fat (they're hidden near where the tenderloin was attached to the inside of the spine).
Trim the Fat End
The fat end of the tenderloin has a large lobe of meat that attaches to the main length. In between these two pieces of meat there's a bit of connective tissue and fat. Use the tip of your knife to trim it out as best as possible.
How to Tie Up the Meat
You now have a whole, trimmed tenderloin, but it's not quite ready to roast yet. First you have to even out the differences in thickness between the fat and narrow ends.
Fold the Narrow End Back
Fold the narrow end of the tenderloin back under itself in order to create a relatively even thickness along the entire length of the tenderloin.
Tie the End in Place
Tie the tenderloin at one-inch intervals using butcher's twine. This is most easily done using butcher's knots, though regular square knots will do.
A Whole Tenderloin, Ready to Roast
Once tied, the whole tenderloin is ready to season and roast. A whole tenderloin weighs between four and five pounds and is large enough to feed eight to 12 people.
Get at the Center Cut (Optional)
The middle section of the tenderloin, known as center-cut tenderloin or chateaubriand, is a large, even, cylindrical piece of meat that weighs between two to three pounds, serving four to six people. It's a desirable cut because it is much easier to cook evenly than a whole tenderloin.
If you'd like, you can trim down the whole tenderloin to just the center cut by cutting off the fat and narrow ends. Those ends can then be reserved for use in another dish, or further sliced to be grilled or pan-seared as steaks.