need particular advice on preparing a beef tenderloin
So I'm hosting a dinner for 4 to which one guest is bringing a (to me) nice bordeaux, a 1996 Pichone Lalande, which is a Pauillac, and which will be prefaced by an Arneis and followed by a Valpolicella. Another guest volunteered to bring meat and has called saying the meat will be a whole (trimmed) beef tenderloin.
Now I've never roasted a tenderloin (or even make filet mignons). Almost always when I make beef I buy hanger steak and when I want to splurge I buy ribeye. The fact that I'd never buy a whole tenderloin myself makes me especially excited have one brought over. But I need advice on what to do with it.
1) one guest keeps kosher, such that I can't use any dairy product or pork or any non-kosher animal product (but it's fine to use my pans, which have rendered many a strip of bacon). The tenderloin is kosher, but I don't have time to buy any further kosher meat or stock. So the sauce for the tenderloin can't include butter, cream, meat stock of any sort, etc. This feels sort of limiting.
2) I've never cooked tenderloin before, and am scared of it coming out too dry.
One suggestion has been to cover the roast in mushroom duxelles, which would add flavor and keep the meat moist. Another idea I had was to drizzle over it a reduction of balsamic vinegar.
I'd welcome adivce of any sort for cooking or saucing this tenderloin. I'm planning to serve it with a potato galette (the pommes anna from Bistro Chez L'Ami Lois as reported by Calivin Trillin) while I'll fill with sauteed ramps, plus some baby vegetables blanced and simmered in veggie stock, and a salad of mixed baby lettuces and fiddleheads. For the Arneis I'm making an appetizer of pissaladiere (slow-caramelized onion tart [sometimes a pizza but I prefer a tart] with nicoise olives and anchovies).
The thing you need to worry about (or, be careful of) when preparing a whole beef tenderloin is to not overcook it, (or undercook it for that matter, because it needs to rest and the temp will rise after you remove it from the oven.) Do not cover it or smother it with sauce while cooking. That will steam it. The browned exterior is one of the joys of roast tenderloin.
I wish I could give you exact advice. You seem like an experienced cook, or at least, diner. Rub that meat with kosher salt, pepper, and a pinch of sugar- and garlic if you like, about 30 mins before cooking. If you have the right equipment, sear the meat on 3 sides before you put it in a hot oven (I'd say 425 unless yours runs hot) for 30 mins or so. Less if it took more than a few moments to sear. In a restaurant convection oven they take about 22 mins for med rare. But home ovens are usually less hot. Squeeze it, probe it, or even nick it open to test because a well done tenderloin is a waste of a lot of money. If the stuff on the bottom of the pan seems like it's going to burn you can pour in a little water.
Then you need to let it rest for at least 10 minutes before serving. You could deglaze the roasting pan with some kosher wine and flavor the jus with good quality balsamic. Too bad you couldn't whisk in some butter, too
I agree with essentially everything Cleo has posted. I would use grapeseed oil. You can leave the meat longer than 30min, it won't dry out. You could also toss some onions and/or carrots in to the pan after the meat instead of the sugar, they will carmelize and add depth to the sauce. Don't use small pieces of garlic, they will burn and leave a bitterness.
However, instead of relying on time or probing the meat to see if it is done, I would strongly, strongly suggest buying/using a 'constant read oven safe' thermometer/probe (for example see the URL). You just shove the probe into the center of the meat (tip in thick part) after browning three sides, stick it in the oven and wait for it to come to temp. and beep. I would pull it out at 125-128 and should drift up to 132-135 - perfectly cooked - as you make the sauce. I am a very experienced home cook and this thing changed my world. I would not even consider cooking a big 'ol chunk of meat without it. Never fails. Always perfect. Learn your temperatures, learn what you like, never worry.
I also strongly suggest taking a look at the meat. If one end tapers off more than a little you need to fold/tuck it over itself to make it a bit thicker or it will overcook before the thicker parts cook (or, if somebody likes it more done than everybody else, leave it).
Sounds like a great meal! And just because I am impossibly jealous - you should decant the Pichon. It is still youngish, but should be awesome. So jealous.
Just one thing to add to this excellent post: I have a thermometer similar to this, and it lets you dial in beef, pork, veal, etc. and then "rare," "medium," etc. All of this cooking temps, to me, are too high, mainly because of the USDA min temp requirements. Consult a good cookbook that doesn't gloss over the subject of cooking temps.
It is hard to get a kosher tenderloin because it needs a very high level of supervision to cut it because of all the veins. In fact many people think it is not a kosher cut. Someone is bringing you something rare.
If you never worked with a tenderloin, don't be surprised if one side is pretty ragged, where many veins have removed. The first time I bought one it was untied and I had that terrible moment when I thought I had been cheated before I did some research.
If it is whole you will need to tie one end so that it will cook evenly. (Unless of course you have several guests who like well done meat.)
Make sure you decant the Comtesse and enjoy!
Most of the advice is sound, but if you are cooking for four, I would cut about 5 inches from the tail (to use later for beef stroganoff)and about 4 inches from the butt end. This should leave you with a chateaubriand, about 7-8 inches of relatively uniform thickness. Perfect for four diners. Many sauces are appropriate, and you can always serve your kosher guest unsauced slices. You will find the butt end (biftek in French) a bit gristley, and best trimmed. There is usually a chunk of gristle about 2 inches from the butt end. I usually trim it out and use the butt pieces as kabobs.