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The Food Lab: How To Make a Foie Gras Torchon (Secret Technique Inside!)
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Did you know that with just $65 and a bit of effort, you can serve your holiday guests the king of all hors d'oeuvres?
I'm gonna go out on a limb here and venture a guess that for the vast vast vast majority of you, this post is gonna seem less than 100% useful. I mean, a cured, fattened duck liver barely cooked and rolled up in a kitchen towel? What the heck kind of a dish is that? How many people even eat foie gras to begin with, mush less at home, and who in their right mind wants to spend three days working on a single cold appetizer?
And fair enough. But if the current state of media is any indication, we love to learn about things we're never going to do for ourselves. We have shows that answer questions like, "can a cockroach survive a nuclear holocaust?" There's an entire documentary about training dragons. And how many of you are prepared for the zombie apocalypse that, to be honest, will *probably* never happen?
By those standards, making a foie torchon doesn't seem so far fetched, does it? And it shouldn't! It is, after all, one of the pinnacles of Western cuisine, combining centuries of exploration into the fields of animal husbandry and breeding, curing and charcuterie, flavor development, and of course general kitchen badassery.
The basic process starts with really good foie gras. Living in the United States, fortunately this is relatively easy to find. There are only two foie farms remaining in the country (the third, Sonoma foie was recently closed due to California law), both of them located in the Hudson Valley in New York, and both of them producing excellent foie gras from very well-raised ducks. (Take an inside look at La Belle Farms here). Once the liver is cleaned of veins, it's cured in a mixture of salt, sugar, and pepper, along with a splash of liquor such as brandy or Sauternes, before being rolled up tightly into a cylinder, typically inside a clean kitchen towel (that would be a torchon in French). After hanging for a few days, it's gently poached, chilled again, then served sliced.
A perfect foie torchon melts on the tongue like the creamiest butter, but with a distinct cured sweetness that forms the perfect balance for a perfumed wine. It's simple to serve—just slice it, put it on a piece of toast, add a bit of dried fruit or preserves, and go—and let's face it, it'll impress your guests.
Foie gras ain't cheap, but it's not out-of-this-world expensive either. A full liver—enough to feed at least 10 to 16 people—will run you $65 if you order it online (I recommend Bella Bella Gourmet, who were kind enough to provide the foie I used for these recipes.
Are you sold yet? Well good, because we're about to dive in. While this is such a classic dish that the technique is pretty much a standard, there are a few tricks I've developed over the past few years to get you to your end in a better, more streamlined manner.
Foie comes in two grades, "A" and "B." The grading standards are self-designated, but generally refer to the amount of bruising there is on the exterior of a lobe, and how many interior veins there are. For things like searing or roasting whole, you'd want to go with an "A" liver, since you don't have the opportunity to remove veins before cooking it. For a torchon, on the other hand, we're going to dive in there and remove all the veins anyway, so a B lobe will do just fine.
De-veining the foie is the most painstaking and frustrating part of the process, but it's easier than it looks. I like to do it with a pair of tweezers and a metal offset spatula, which I find is less likely to accidentally cut through a vein than a normal paring knife.
The key is this: DON'T WORRY IF YOU MESS IT UP. Room temperature foie gras is like play doh—extremely forgiving. Even if you completely mangle it trying to get those veins out, you can always push it back into shape and nobody will be the wiser.
Once you've got the major veins out, go back in with your spatula and start pressing the foie around, searching it for any more tiny veins or burst blood vessels that'll leave unattractive red spots in your finished torchon.
Once the veins are out, you're ready to cure.
The curing step is the one in which I personally take most issue with existing recipes. Some start with an overnight soak in milk, which accomplishes... nothing, other than to slightly lighten the color of the liver as it leaches out a bit of blood that you may have missed. If you feel like doing it, it won't hurt, but I personally skip this step—the flavor of your torchon will be the same.
The second point in which I find problems is that most recipes have you season your foie by eye, sprinkling it with salt and pepper until it seems right. Any professional charcutier will tell you that the key to a successful, tasty cured meat preparation is to get the proportions of curing agent precisely correct. There's nothing more important in food than proper seasoning, and since you can't exactly taste as you go, eyeballing it just ain't good enough.
These are the proportions we're aiming for. All ingredients are listed as a percentage of the weight of foie gras you are starting with.
- 1.5 % salt
- 0.5% sugar
- 0.25% pink curing salt (optional, but this helps it retain color and produces a unique "cured" flavor)
- 0.2 to 0.25% white or black pepper
If you work in imperial measure (like ounces and pounds), figuring out these amounts may seem a bit daunting because it is*. Don't make it harder for yourself than it needs to be. If you're making charcuterie, work in metric. It makes these calculations simple. For example, say I have a 500 gram piece of foie gras (about average). That means I need 7.5 grams of salt (500grams x 1.5%), 2.5 grams of sugar, 1.25 grams of pink salt, and 1 gram of pepper.
*See here for more information about why the United States' system of measurement is, well, idiotic.
Now we hit a little snag: my scale only measures in full grams, which means that to measure 1.25 grams of pink salt, I have to estimate it as somewhere between 1 and 2 grams. This doesn't work for me. I need to be more accurate than that.
What's the solution?
Simple: Just make a larger batch of curing solution, say 10 times the amount I need. When measuring larger quantities of material, the relative precision of my scale goes up. Rather than measuring 7.5 grams of salt and 2.5 grams of sugar, I just measure 75 grams of salt and 25 grams of sugar and so forth. Once all the seasonings are measured, I mix them all together, then grind them up into a homogenous powder.
To figure out how much I need for the foie, I add up their total percentages. In this case, I know that I'll need 2.5% of this combined curing solution. So for a 500 gram lobe of foie, that comes out to 12.5 grams of curing solution. Even if I'm not 100% accurate this time (as I'll have to estimate between 12 and 13 grams), the degree to which I'm off will be spread across all of the ingredients, which means that any single ingredient will be off by at most 4% or so, and that's an accuracy range I can deal with.
You all with me?
Roll With Me
Next up is another step that I find can be easily streamlined. While many recipe call for seasoning the foie with the curing mixture then letting it rest overnight before rolling it into a cylinder, I've found that by rolling it straight away, you actually get better end results, as immediate rolling will help prevent oxidation from occurring on the surface of the foie. Foie gras is also softer before it's been cured, making it easier to roll and prevent air bubbles from forming.
I spread my foie on a triple layer of plastic wrap (easier to work with than parchment paper), carefully work it into an even square, then sprinkle on the cure using a fine mesh strainer to get a perfectly even snow-like coat.
Anyone who's ever tried to make a foie torchon the completely classical way will tell you that the most difficult step—the one that takes the most practice and doles out the most frustration—is rolling the foie into a tight cylinder. You are not only working with a rather unevenly shaped, soft, greasy object, but you're also trying to squeeze out every single last air bubble inside. The goal is a completely solid cylinder of foie.
Typically, you start this by carefully lifting the trailing edge of the parchment or plastic wrap to lift the foie onto itself, slowly working it jelly-roll style into a cylinder. If it starts to get too warm and stick to the plastic or melt, you have to shove it in the freezer for a few minutes. Typically, you end this by smearing foie over your cutting board, grappling with greasy fat-coated fingers with an unwieldy and misshapen tube, cursing your ancestors for ever bringing you to such a frustratingly uncooperative earth before manhandling your tube of liver into a shape that is at least passably cylindrical.
I was undergoing this very process a few days ago when it hit me: Rolling a foie torchon is not all that different from rolling a sushi roll. if a reticulated bamboo mat could help me roll tight, beautiful kappa-maki, couldn't it do the same for my foie?
Yes, indeed it can. This is the kind of trick that I'd give my right pinky to be able to go back in time and whisper in my own ear back when it was my lowly line-cook garde manger job to make three of these guys every night. Just think of the amount of time I could have saved on making torchons and spent drinking icy cold PBR's in the walk-in instead!
Tighter and Tighter
Now that we have a passable cylinder, our next job is to squeeze out any and all air bubbles. We do this by wrapping the whole thing in cheese cloth, and tightening it until it can be tightened no more.
My method for this is to do it guitar-string style, tying off both ends with butchers twine, the winding a long piece of twine around one end, slowly working it down towards the foie, squeezing the foie tighter and tighter as I wind. By the time its done, the torchon is just beginning to show spots of fat oozing out and has the resilient bounce of an inflated bike tire.
And now, we hang it (in order to help it keep its shape), and wait.
Over the course of the next day (or few days, if you prefer), as your torchon hangs in the refrigerator, the salt and pink salt slowly get to work curing the foie, altering the shape of its proteins so that they become firmer, more opaque, developing flavor and texture. Once sufficient time has passed, your foie will have a tender, fatty texture similar to butter, but with the unique ability to hold its shape just until you bit into it or press a disk onto your tongue.
To Cook or Not To Cook?
At this stage, the most classical of recipes will have you poach your torchon in a bath of sub-simmering hot water for about 20 minutes, long enough to bring the whole thing into the range of 130 to 140°F, effectively cooking it. More modern recipes, such as Thomas Keller's go for a much, much shorter cooking time—about 90 seconds. Tasted side by side, I've always preferred the shorter cooking time. The foie is denser, has a more buttery texture, and doesn't leak as much fat when you slice it or eat it.
I always wondered why this was until I came to what was a pretty obvious realization: Thomas Keller's 90-second poached torchon is essentially uncooked. I stuck a thermometer into a torchon during its simmer and measured the internal temperature. It started at around 40°F, and finished exactly where it started. Aside from the outer few millimeters, absolutely no cooking occurs in a 90-second poached foie. No wonder the texture is so significantly different—we're essentially eating raw cured liver here!
There is, however, a good reason to poach the foie, even if it's only for a brief period: The exterior layers soften enough that you can wrap the cheesecloth even tighter, giving you a better looking finished product. That Thomas Keller poach is really all about appearances!
Once the second poach is done, you're essentially home-free. Hang it in your fridge just long enough to let it firm up again (overnight is best), and you're ready to slice and serve.
I slice off the ends, saving the scraps for myself as kitchen treats, then carefully unroll the center. To get the smoothest slices, dip a thin-bladed knife into warm water before slicing. It should glide through like a, well, like a hot knife through butter. You'll notice that the outer edges might be a little discolored due to oxidation. This won't affect flavor, but for a prettier look, use a biscuit cutter or ring mold to punch out perfect circles.
Unused portions can be wrapped tightly in plastic for a few days, or cryovacked and frozen for up to several months.
What To Serve it With
Foie torchon is excellent on its own with just a sprinkle of crunchy sea salt and a glass of wine—Sauternes is the classic pairing, but port, Riesling, brandy, sherry, or even champagne will all work well—but most folks like to serve it with something a little sweet to complement its rich fattiness.
My personal favorite is bits of toast cooked slowly in butter—for perfectly sized round pieces of toast, use a ring mold one-size larger than the one you use for the foie, as the bread will shrink slightly as it toasts—and a topping of finely chopped prunes soaked in a simple syrup made with equal parts cognac and sugar. It's sweet but not cloying, and the alcohol adds a pleasant bite to the mix.
Other things you might like are fruit preserves, good quality balsamic vinegar (or a balsamic syrup made with sugar and balsamic vinegar), dried fruits, nuts, honey... basically anything you'd put on a cheese plate will do well with foie.
Like I said, making a torchon is not the easiest thing in the world, but it is certainly one of the most satisfying kitchen tasks. It's the ultimate in hors d'oeuvres, using not just one of the finest ingredients money can buy, but also showcasing your skill as a craftsman.
I can't tell you how awesome it feels when you make that perfectly tight cylinder, squeezing it with the twine, feeling the pressure build inside, then touching it and feeling it harden as it cools in the fridge. I found myself involuntarily wandering over to the refrigerator, just to hold it in my hands, to smell its sweet aroma coming out through the cheese-cloth, almost zombie-like in my involuntary actions.
Perhaps we will be seeing a foie-induced zombie apocalypse some time after all.
Get The Recipe!
About the author: J. Kenji Lopez-Alt is the Chief Creative Officer of Serious Eats where he likes to explore the science of home cooking in his weekly column The Food Lab. You can follow him at @thefoodlab on Twitter, or at The Food Lab on Facebook.