The secret to perfect fries—crisp on the outside and soft within—is to “fry” them twice, first to cook through, then to crisp and color. The first step is called blanching rather than deep-frying, since the temperature of the oil (300°F) is sufficient to soften, but not brown. (If you tried to cook them at a high temperature the whole time, the outsides would burn before the insides were cooked through.) The second step involves true deep-frying: the oil is brought up to 350°F—hot enough to quickly brown the outside without needing to cook the interior further. As with the sautéed rosti (page 329), the potatoes are soaked in water before cooking to remove excess starch, then dried thoroughly. Whenever deep-frying, remember that the oil should be maintained at the proper temperature, so you will need to adjust the heat as necessary. Unless you have a deep-fryer, use a cast-iron pot; it holds its heat better and distributes heat more evenly than other types. Also, frying can leave oil marks on stainless steel and other surfaces that are difficult to clean. To keep the temperature from dropping too much, add potatoes in batches; this will also ensure that they fry evenly and quickly. If the temperature spikes at any time, cool down the oil by adding some room-temperature oil to the pot. Be sure to salt the fries immediately after removing from the oil, when they are still piping hot. Any other seasonings (such as the lemon zest and rosemary below) are purely optional. Homemade mayonnaise (page 95) is an indulgent option for dipping. Or drizzle with malt vinegar for a tangy taste.

　　

Ingredients

Serves 6

　　6 russet potatoes (about 3 pounds total)

　　2 quarts peanut or cold-processed sunflower or safflower oil

　　1 to 2 tablespoons rosemary leaves (optional) or small sprigs

　　Julienned zest of 1 lemon (page 34, optional)

　　Fine sea salt

　　

Step 1

Soak potatoes Peel potatoes and square off sides and ends. Cut lengthwise into 1/3-inch-thick slices, then cut into 4-by-1/3-by-1/3-inch sticks. Place in a large bowl and add cold water to cover by 1 inch, then let soak in the refrigerator at least 4 hours or up to 24 hours. Drain potatoes and spread on a clean kitchen towel and dry completely, patting off as much water as possible.

　　

Step 2

Blanch potatoes in oil Line baking sheets with a double thickness of paper towels. Heat 2 inches of oil in a heavy stockpot over medium heat to 300°F on a deep-fry thermometer. Working in batches and using a spider, lower potatoes into oil (the temperature will drop significantly, to about 270°F, and slowly climb up again) and stir to separate. Cook just until softened (test one by breaking in half; it should be almost completely cooked through), but not brown, about 3 minutes. Use a spider or slotted spoon to transfer to one of the prepared baking sheets to drain, spreading in a single layer. Allow oil to return to 300°F between each batch. (The potatoes can be blanched and left to drain on the prepared baking sheets for 4 hours in the refrigerator before finishing, replacing the paper towels as necessary.)

　　

Step 3

Fry Heat oil to 350°F. Again working in batches, add blanched potatoes to oil (the temperature will drop to about 340°F) and stir to separate. Cook until golden brown, 4 to 4 1/2 minutes; if desired, add the rosemary and lemon zest during the last 20 seconds of cooking. Use a spider or slotted spoon to transfer to prepared baking sheets to drain (replace paper towels if you are using the same baking sheets as above). Allow oil to return to 350°F between each batch.

　　

Step 4

Serve Sprinkle with salt and serve immediately.

　　Reprinted with permission from Martha Stewart's Cooking School: Lessons and Recipes for the Home Cook by Martha Stewart. Copyright © 2008 by Martha Stewart. Published by Crown Publishing. All Rights Reserved.Martha Stewart is the author of dozens of bestselling books on cooking, entertaining, gardening, weddings, and decorating. She is the host of The Martha Stewart Show, the Emmy-winning, daily national syndicated program, and founder of Martha Stewart Living Omnimedia, which publishes several magazines, including Martha Stewart Living; produces Martha Stewart Living Radio, channel 112 on SIRIUS Satellite Radio; and provides a wealth of ideas and information on www.marthastewart.com.