Sous vide is French for cooking in a vacuum, placing sealed meat or veggies in water held at an exact temperature. Because this precision requires high technology, the method was solely for chefs—until the $450 SousVide Supreme arrived.
Sous What Now?

Think of sous vide as cooking from the inside out, rather than the outside in.
When the Coen Brothers were making The Big Lebowski, they couldn't for the life of them figure out how to fling the ringer—a briefcase supposedly containing $1 million but actually holding Walter's dirty undies—in a graceful arc from the Dude's moving car. It sounds easy, but it's physically impossible. They were about to give up when the sage-like Jeff Bridges suggested shooting it backwards. Eureka. They filmed the bag toss, its perfect trajectory, falling into the slowly reversing automobile, and made cinematic history.
Sous vide is a lot like that. Instead of burning the crap out of your extra-thick filet mignon in a pan, perhaps tossing it into a hot oven afterwards, all with the hope of hitting a target internal temperature of 130║F almost by chance, you vacuum seal the lightly salted raw meat and stick the bag into the "water oven," raising the temperature of the entire cut to 130║.

Once the ideal "medium rare" is reached, you sear the outside for a pleasing Maillard-effected crust.

Your steak is perfect. And you can't fail. Seriously, you can do this 1000 times and never screw up. Because of sous vide's precision temperature, you can let meat sit for hours without fear of it overcooking. Sous vide is (mostly) moron-proof—high science brought down to home kitchens that may or may not be worthy. If you eat medium-rare steak at home at least once a week, you basically need this.
In some ways, sous vide is the next obvious kitchen tool, like its predecessors the microwave, the convection oven and the induction cooktop. It's a unique tool that could easily go from exotic to commonplace in just a few years. As you'll see, the microwave comparison is perhaps most apt, since they're both self contained, make simple meal prep easier, and function on a fool-proof, "set-it-and-forget-it" basis.

The only catch is, when cooking sous vide, you have to vacuum seal everything, or—as I discovered—buy food that comes pre-sealed. The SousVide Supreme doesn't have its own sealer, so you need to buy a FoodSaver or something like it, which can be expensive. I was loaned a Reynolds Handi-Vac, which was finicky but at least affordable. The sad news is that Reynolds discontinued it, so if you own one or buy one on eBay, make sure to stock up on bags. (Here are some official details on that.)
Beyond Steak

My crash course in sous vide cooking came from this amazing, nerdy practical guide by Douglas Baldwin, a comp-sci/math guy at the University of Colorado, Boulder. He covers the basics of cooking meat and other protein in a sous vide bath as thoroughly as one could ask for from a guy busy getting his PhD in Applied Mathematics. I encourage you to read it, though it's basically a discourse of temperature and time, the only two factors in sous vide cooking.
Seriously, that's really all there is to the SousVide Supreme. You set the temperature, in Celsius or Fahrenheit, and then you set the timer. That latter part is optional if you own a clock, since it takes hours, sometimes days, to overcook anything. I prepared many meals in there, and only managed to ruin one dish. I left some chicken cooking overnight, mostly to see what would happen if I did. The meat just became inedibly flaky.

There is a very nice, very expensive cookbook by Thomas Keller (and his team of cooking/writing geniuses) that explains the miracles sous vide is capable of performing. I did not use that book during this test, in part because I wouldn't have had any money left over to buy food, but in part because we're talking about you and me, not TK and the CIA posse. If you will likely be creating "cuttlefish tagliatelle with palm hearts and nectarine" or maybe "squab with piquillo peppers, marcona almonds, fennel and date sauce" on a regular basis, then a) I pretty much hate you and b) why the hell are you taking advice from me? What I can tell you is what an enthusiastic, experienced and adventurous home cook could possibly do with this thing on an ongoing basis. That, it turns out, is the trick. It's not what you can make, it's what you can keep making, day in and day out. Here's what I cooked, and whether or not SousVide Supreme is worth having on hand for best results.
Food Porn

Eggs: Hard boiling an egg is easy, but getting the perfect custard-like consistency of a gently soft-boiled egg is not. This baby can do it blindfolded. Just set the temperature to 148║ F, wait for the thermostat to beep, then toss in a few eggs, no vacuum sealing needed, since nature already did that. I made a spaghetti carbonara the other day that was absolutely perfect, in large part due to SousVide Supreme. Since I don't know of any other way to get the perfect soft-boiled besides maybe timing and praying, I'm going to say SVS wins this round: Worth It

Duck breast: Lord love a ducků and so do I. But duck is another classic overcookable meat. I set mine for 150║ and frankly, I still think I could have gone lower. Once it came out of the vacuum-sealed bag (which it was conveniently packaged in when I bought it, along with a cheap but not terrible l'orange sauce), I stuck the breast in a hot pan, searing the fat out of the skin side, and then browning the rest of the breast with the rendered fat. Verdict? I've overcooked enough duck in the past to say yes, this kind of control is appreciated: Worth It
Rack of lamb, rib roast, and other tender roast meats: Steak and duck are just a few of the "tender" meats that benefit from sous vide. I didn't try these others (partly cuz they're so damn expensive), but my experience with them in ovens, sometimes undercooking, sometimes overcooking, tells me how nice it would be to have the ability to reach a fixed internal temperature, even if it took many hours. But is it worth it? These are not foods one prepares too often, and there are tried-and-true ways to roast them in an oven, especially a convection oven with more controls. So I am going to have to say: Not Worth It

Short ribs and other tough meats: Here's another example of getting something different than what you can achieve in an oven. I love to brown the hell out of my short ribs, then braise the hell out of them in wine and mirepoix for 4-6 hours, in an oven, at a temperature of 325║. With sous vide, you can slow-cook short ribs at 135║ for two days, rendering them softer but still rare. The meat is almost prime-ribby. I actually browned them before their sous vide cooking process, so they could be eaten immediately out of the vacuum bag. Verdict? I've never tasted slow-roasted meats like this—it was very good, and there's something to be said for transforming a rude cut of meat into a fine steak, but my in-oven slow-cooking method is as fool-proof, and has the added benefit of creating a carmelized sauce to go with it. It's a Draw

Fish: One of the funny things about sous vide fish is that so many fish come frozen vacuum sealed in plastic, often already steeped in marinade. You just throw the whole bag in, still frozen, wait an hour, and pull it out. There it comes, spilling out of the bag ready to eat, every bit a sci-fi—or at least 1st class airline—fantasy. But anybody interested in buying a SousVide Supreme will have no problem broiling or poaching fish to their desired doneness, and you don't sear a cooked fish as you would a cooked steak, so the sous vide process is a liability, or at least a limitation. Not Worth It
Vegetables: Veggies are another strangely gray area. I mean, I don't have any problem steaming, boiling, roasting or pan-frying vegetables, but there's some allure to the fact that you can cook them in a perfectly sealed environment, thereby preserving the very essence of that vegetable. (I'll admit, the allure doesn't pull me too strongly.)

I tried artichokes and beets. Nailing the beets was easy, since a beet is the same from outside in, so you just leave them in there for 90 minutes or so they're cooked through at 183║. And when they come out? They taste like cooked beets.

But those artichokes, ugh. Not only do the heart and petals cook differently, they can be quite different from one to the next. Also, they float. At least the big old leathery dead-of-winter flown-in-from-God-knows-where prickly sons of bitches that I tried. I've cooked artichokes for ages, even carefully charring them on the grill, but in this case I assumed the set-it-and-forget-it approach was good enough, and it wasn't. I eventually did get the artichokes cooked through, but I had to pop them out of the bag to check them, and I had to sit a heavy plate over the top of them to get them both underwater. Those two specific issues—and the general fact that I was $#@!ing around with artichokes for several hours—combine to kill any advantage of this over the old pot-boil method. Not Worth It (though I am sure Thomas Keller's artichaux are to die for)
That Sweet, Succulent Bacteria

I might add that there's a food-poisoning angle to sous vide that could be a problem, but only if you're totally oblivious to the issues. Usually, you cook food at a bacteria-scorching 300║ F or higher. With sous vide, you're often operating in that weird borderland of 130║ to 140║, so you have to be far more careful. Generally speaking, anything cooked so that the center reaches 130║ or higher is fine, and anything you sear the daylights out of after you sous vide it is fine, too.
If you want to research this issue further, I suggest starting with Baldwin's practical guide (specifically, the sections on "Safety" and—my favorite—"Pathogens of Interest"). In reality, the key is to exercise the same caution you normally should, only with extra vigilance. Don't reuse knives and utensils used for prepping raw meat, don't let food sit around at room temperature for very long, and don't undercook anything of dubious origin.
The Next Microwave

SousVide Supreme is the first home-targeted sous vide machine that I am aware of, certainly the first getting any kind of attention in the US. It's not the last. I know that precise temperature control does cost money, but technologies like this get inevitably cheaper, and I predict slightly smaller units selling in the $100 range in the next 2-3 years. I have a $100 rice cooker that gets a regular workout, and a brand new $100 Max Burton inductive burner that gets daily use. On the other side, I've got a $100 deep fryer that comes out twice or three times per year for occasions that demand Belgian frites, and a really nice slow cooker we have seriously never used.

My point is that, within the spectrum of fairly specialized cooking devices that a kitchen adventurer like me would own, the SousVide Supreme sits on the more useful end. But $430 is too much, and the size of the thing too great, to be justifiable for any but the most voracious of carnivores.

Five years from now, you will have a freezer full of pre-sealed pre-seasoned raw meats and fish, and you will toss these into your precision water bath like you throw something in the microwave now. We won't think about sous vide as a gift from science, just like we no longer consider it crazy that we "zap" food with radar microwaves. Sous vide will simply be an option, at least for those who want it. As great as this convenience will be for avid cooks, I hope the experience doesn't become mundane. In the meantime, you could spring for the SousVide Supreme, which works as advertised, or you can hack yourself something close if not perfect. Either way, you will love it—especially the steak—but don't expect a miracle. This won't turn you into the next Thomas Keller unless that's who you're destined to become anyway.

First "affordable" home sous vide cooking machine, offering a unique set of cooking capabilities that aren't easy to emulate without precision equipment

Extremely easy to use, and works exactly as billed

It will not make you a great cook overnight, though it will help you achieve goals you may already have

$450 is still too much for most home cooks, especially for something that they might not use often enough

Vacuum sealer equipment sold separately (and can be costly)

As large as a bread-maker or turkey roaster, equally hard to store when not in use

Interface not great; display lacks count-down timer, and buttons are sometimes unresponsive
Shout out to John Mahoney, who reviewed the SVS at Popular Science. If you're seriously considering buying this, it makes sense to read both of our takes; we think differently, but are equally in search of great culinary experiences.
Special thanks to reader Michael A., who alerted me to the existence of the SousVide Supreme after reading my holiday gift guide for home cooks. He also told me about this slightly cheaper SV controller, a little too science-projecty for a Giz review, but possibly a great alternative for someone with enough cojones.
A quick note about the Coens: Though I've come across it on several occasions, one account of the Coen Brothers' ringer-toss challenge can be found in the source-rich—but literarily unsatisfying—The Big Lebowski; The Making of a Coen Brothers Film. Coulda been way better, but still, it's required reading for die-hard Lebowski/Coen fans.
And finally, a little self promotion: If you like my style of food porn, and my cooking chatter, take a peek at my online cooking diary, You Make It You Eat It.

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