Cut potatoes into 1/4-inch-thick slices with a waffle cutter.
Pour vegetable oil to a depth of 4 inches in a Dutch oven, and heat to 325°. Fry potato strips, in batches, until lightly golden, but not brown, 4 to 5 minutes per batch. Drain strips on paper towels.
Heat oil to 375°. Fry strips, in small batches, until golden brown and crisp, 1 to 2 minutes per batch. Drain on clean paper towels. Sprinkle with salt, and serve immediately.
Note: For testing purposes only, we used Wesson vegetable oil.