French Fries
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.