"A starchy potato, like an Idaho, is best for French fries. Cook the fries twice, first at a lower heat, which assures the center of each fry is cooked through, and then at a higher heat, so they also become crispy and golden brown. By the way, the French usually serve their fries with homemade mayonnaise. I suggest you serve them with whatever you like the best. "
3 Idaho potatoes (also known as Russet potatoes), peeled
Refined peanut oil for frying OR canola or safflower oil
Salt
In a large bowl, prepare an ice bath. To the ice bath, add a tablespoon of lemon juice.
Peel the potatoes. Cut the potatoes into 1/4-inch slices. Immediately put the cut potatoes into the ice bath. When all the potatoes are in the bath, move them around in the cold water. Drain the water. Add clean water to the bowl, ice and another tablespoon of lemon juice. (That procedure will rinse off the excess starch.)
When cutting the peeled potato into slices, first square it off to keep it steady, then cut 1/4-inch discs, then cut the discs into 1/4-inch strips.
For the first fry:
In a deep-fryer or Dutch oven, heat the oil to medium-low, 325°F. Use a candy or frying thermometer to check the temperature.
While the oil is heating, drain the fries and dry them well in a clean kitchen towel. (Wet potatoes would be dangerous if added to the hot oil.) Line several sheet pans with brown paper bags so they are ready when the fries come out of the oil.
When the oil reaches 325°F, add the first batch of dried potatoes, do not crowd them, and cook for 6 to 8 minutes, until they are soft and have taken on a slightly golden color. Remove the fries from the oil using a wire mesh spider skimmer or slotted spoon, and transfer to the paper-lined pans to drain. Repeat with the second batch.
For the second fry:
Now, heat the oil to 375°F. Return the fries to the oil and cook for another 2 to 3 minutes or until the fries are golden brown and crispy. Drain on clean paper, salt generously, and serve.