Twice-cooking these fries yields the tastiest results: The first round cooks the potatoes and removes some of the water and starch, while the second makes them nice and crisp. Prep and Cook Time: about 1 3/4 hours, plus at least 2 1/4 hours for chilling and cooling.
Though it's pricey, peanut oil creates exceptionally delicious fries. A deep-frying thermometer is essential for gauging oil temperature so that the potatoes cook evenly. We like the Taylor Classic Candy and Deep-Fry Analog Thermometer ($13; available at housewares and home improvement stores), which comes with a built-in pan clip. The parsley needs to be completely dry to coat the fries without getting them soggy; whirl sprigs in a salad spinner, then wring in paper towels. If you're making burgers along with the fries, finish the fries through step 2, then start on the burgers.