Last year, I became enamored with the sous vide process and started down the path. I believe Peter Van Es is well experienced with the process.
For those wanting to try it out, the FIRST thing you'll need is a "food saver" vacuum sealer. Food Saver is a brand name, and they sell these at Costco, Bed Bath and Beyond, Amazon and related. They allow you to package food in vacuum-sealed bags, preventing freezer burn. They are essential for the sous vide method since you need your food sealed in plastic with no air. But they are more than that; with one of these, you can take advantage of sale prices on meats and other freezable products and retain their integrity over much longer periods than say, a zip-lock bag. I bought my Food Saver while on sale at Costco, FoodSaver FM5480, last year. I think you can find that for around $125-$175 depending on sale, vendor, etc. There are less costly and more costly ones depending on features. Your ongoing expense will be the bags, and generic bags work fine.
Once you get the hang of the vacuum sealer (not too difficult if you own and maintain a Pagoda!!!) the next step is the sous vide machine. Basically, this is a heater and pump assembly that clamps onto a pot or on a cooler, and heats and circulates the heated water at extremely precise temperatures. One noted brand and the one used by the Will at PUB this past weekend was made by Anova. They make several models, running around $120. When I was searching for one the other day, (after that tenderloin last weekend, I jumped back on the sous vide wagon...) I went searching at Amazon...and one by Wancle showed up at a "flash sale" and I ended up buying the Wancle unit here
http://a.co/h0ZC1t4 for just $89.95. Today, it is $109.99. As it just arrived I won't be able to test it until tonight or later...
UPDATE: I've got the machine going right now. If you go to the Wancle website, and to the product listing http://www.wancle.net/product/077.html and then touch the USA flag, it will take you to another "Flash Sale", so if you enter Amazon that way you may still get it for $89.95.The basic gist of sous vide is precise cooking. Do you want a rare steak? That's 130 degrees F. But it in the water bath; it can't get overcooked since the water is exactly 130 degrees; most of the sous vide units maintain the water temperature quite accurately. So, cook it for 2 hours or 6 hours--won't be overcooked. Turn your back on a NY strip on a grill and your $12 a pound steak will be charcoal in minutes.
After our tenderloins last weekend came out of the water bath, they were momentarily put on the grill/smoker for a little extra crust/flavor/finishing.
My cousin is a chef, with 30+ years of experience including that in many famous restaurants in NYC, and two Michelin *** restaurants in France and Switzerland. He told me that it's the only way to cook ten tenderloins for a crowd perfectly (as Will did), but "I can cook a tenderloin perfectly w/o one". I reminded him of his experience, and the most of us don't have that, so a little help from a machine goes a long way. He then conceded that maybe a sous vide machine is OK to have...