Thomas Keller, the chef-owner of The French Laundry and per se, is the only American-born chef to have two
three-starred Michelin restaurants. In addition, he has Bouchon and Bouchon Bakery in Yountville, California,
and Las Vegas and another Bouchon Bakery in New York. His newest endeavor is Ad Hoc, a casual
dining establishment in Yountville. He is the author of The French Laundry and Bouchon.
Why sous vide? You can, and should, ask the same about any technique. Why sauté,
why roast, why grill? Yet we don’t think to question these techniques, because they
have been around for so long. Sous vide techniques are new, and so we’re naturally
a little quizzical, even skeptical. The answer is: we use sous vide because
it allows us to achieve specific results that can be achieved only this way.
Sous vide is not complicated or mysterious, but rather straightforward and exact.
Like all cooking techniques, it is defined by a temperature-time equation: a
given temperature is applied to food for a given time. The two basic facts that
distinguish sous vide from the other cooking techniques are these: we vacuum-pack
the food in plastic (using a vacuum-packer), and we cook it in water that rarely
exceeds 185°F, well below simmering, and usually a good deal lower.
We program and maintain temperature with an immersion circulator.
Sous vide is no more complicated than that. And it gives us the extraordinary
ability to cook food at the same temperature we want it to reach. When we
use most other cooking techniques, we subject the food to temperatures far
hotter than we want that food to be. When we roast a beef tenderloin, we
may only want it to reach 125°F at its center, and yet we put it in an
oven that’s 225°F higher than that. To cook that same beef tenderloin
sous vide, we would vacuum-pack it and put it into 125°F water. Moreover,
when you use a high-heat method such as roasting, the exterior of the
meat gets very hot, past well-done, and inside you get successive rings
of well-done, medium-well, medium, and rare. With sous vide, our entire
tenderloin, not just the center, is the temperature we want it to be.
Cooked sous vide, nongreen vegetables, such as carrots and turnips, emerge
with no loss of flavor to the cooking medium, nor do they fall apart.
Fruits such as watermelon and pineapple acquire an unusual, wonderfully
dense texture when compressed by vacuum-packing. Pale fruits such as
apples and pears don’t oxidize and their color stays vivid, and fruits
such as cherries take on a gorgeous translucent appearance.
These are a few of the many wonders of sous vide. Because sous
vide simplifies so many aspects of cooking, I believe it will
one day be as familiar to home cooks as roasting or frying is now.
Microwaving food was once unfamiliar, after all, and sous vide, in my
estimation, has many more applications than does the microwave oven.
Sunchokes are very sweet and rich, so we pair them with the sharp,
peppery flavors of arugula and three types of radishes, which are gently
pickled and cooked sous vide. The arugula is blanched and pureed, then
combined with a basic creamy vegetable stock that is thickened with
beurre manié and egg yolk to make a savory pudding. My favorite
element in this dish is the radishes. The sous vide technique really
sets their vivid color and cooks them in a way that leaves them powerfully flavored.
150 grams water
75 grams champagne vinegar
75 grams granulated sugar
4 large red French breakfast radishes
4 Flambeau radishes
4 icicle (white) radishes
50 grams unsalted butter
50 grams thinly sliced Spanish onion
400 grams thinly sliced peeled sunchokes
4 grams granulated sugar
12 grams kosher salt
1 kilogram Chicken Stock
100 grams heavy cream
300 grams arugula leaves
70 grams sliced shallots
1 bay leaf
2 thyme sprigs
100 grams Vegetable Stock
100 grams heavy cream
5 grams kosher salt
10 grams Beurre Manié
10 grams beaten egg yolk (about ½ large)
100 grams Clarified Butter
100 grams Brioche, frozen and cut into ⅛-inch dice
For the Radishes--
185°F; 25 minutes
Bring the water and vinegar to a boil. Add the sugar and stir to
dissolve. Remove from the heat and chill over an ice bath until cold.
Meanwhile, rub the radishes in a damp towel to clean. Trim the ends
from the radishes. With a #12 parisienne baller, cut balls of red radish.
Cut the Flambeau radishes into small disks. Cut the icicle radishes into
oblique (roll-cut) shapes.
Place the 3 types of radish in separate bags. Pour in enough of the
liquid to just cover the radishes and vacuum-pack on medium.
Cook at 185°F for about 25 minutes; the radishes should still
have some crunch. Cool in an ice bath.
To complete: Drain the radishes and let dry on C-fold towels.
For the Soup:
Melt the butter in a saucepan. Add the onion and sweat until completely soft.
Add the sunchokes, stir in the sugar and salt, and add the chicken stock.
Bring to a simmer and cook until the sunchokes are completely soft and the
stock is reduced by about half. Add the cream and bring to a simmer.
Puree the soup in a Vita-Prep, then pass through a chinois or
fine-mesh conical strainer. Refrigerate if not serving right away.
For the Arugula Pudding:
Blanch the arugula leaves. Cool in an ice bath. Drain, wrap in a towel,
and wring out as much water as possible.
Put the arugula in the Vita-Prep with 4 ice cubes (the ice will
help the arugula maintain its color). Puree, then pass through a chinois
or fine-mesh conical strainer. Set aside.
Heat a film of canola oil in a saucepan. Add the shallots and sweat
until softened, about 3 minutes; they should not develop any color. Add the bay
leaf and thyme and cook gently for another 3 to 4 minutes. Add the vegetable stock
and cook for about 3 minutes, until the shallots are very soft. Add the cream and
salt. Reduce by half, then strain through a chinois or fine-mesh conical
strainer into a small saucepan.
To complete: Bring the cream mixture to a simmer and whisk in
the beurre manié. Keeping it at a low simmer, cook for 15 minutes to remove any
taste of raw flour. Whisk in the egg yolk. Remove from the heat.
Using two parts arugula puree to one part cream base, stir the puree
into the cream and heat over low heat.
For the Croutons:
Heat the clarified butter in a sauté pan. Add the brioche and stir to color evenly
to a golden brown. Season with salt, and drain on C-fold towels.
Reheat the soup if necessary. Place a spoonful of the pudding, some radishes,
and the radish sprouts in the bottom of each bowl. At the table, pour the soup
around the garnishes. Sprinkle the croutons on top.
Makes 10 servings
Copyright © 2008 by Thomas Keller. Reprinted from Under Pressure
with permission from Artisan.
For a detailed description & pricing info click here.
In Under Pressure, Thomas Keller shows us how sous vide, which involves packing food in
airtight plastic bags and cooking at low heat, achieves results that other cooking methods simply cannot--
in flavor and precision. For example, more...
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