Wash and scrub the potatoes thoroughly. I prefer them unpeeled, but feel free to peel them if preferred. Cut the potatoes into 1/3-inch slices and then slice into 1/3-inch sticks.
Fill a large bowl with water and ice and soak the potatoes, fully submerged, for about 30 minutes. This will prevent the potatoes from oxidizing and help remove the excess starch.
Heat a large Dutch oven or a deep fryer with oil to 325 degrees F. Use a deep-fry thermometer to get it to the right temperature.
While the oil is heating, remove the potatoes from the water and pat them dry with paper towels to remove any excess water.
Add about 2 cups worth of potato sticks to the oil, do not over crowd them. There should be at least a finger of oil above the potatoes. Cook the potatoes for about 5 to 7 minutes or until they start to lightly brown. Transfer them to a rack, shaking off any excess oil. Repeat with remaining potatoes.
Increase the heat of the oil to 350 F degrees.
Cook the potatoes a second time, same as before, about 2 cups at a time, for an additional 2 minutes or until crispy and golden brown. Remove them from the oil, shaking off any excess oil, then place them in a bowl. Season lightly with salt and pepper. Repeat with the remaining potatoes.