Peel potatoes (or lightly scrub if desired), then cut into 1/3-inch slices and then into 1/3-inch sticks. Place the potatoes in a large bowl filled with water as you cut them to keep them from discoloring.
Soak the potatoes for at least 30 minutes or up to 24 hours in the refrigerator. This will remove the excess starch from the potatoes.
Fit a heavy stockpot with a deep-fry thermometer. Heat the oil over medium-high heat to 275-300 degrees F. Have ready a rack set over a baking sheet