Begin by washing the russet potatoes thoroughly, ensuring they are clean but not peeling them. This skin adds flavor and texture. Next, set out a large bowl filled with ice water and grab a mandoline slicer.
Adjust your mandoline slicer to the julienne setting. Carefully slice the potatoes into thin julienne strips. The thinner, the better! As you cut, place them directly into the ice water. This helps to prevent browning and removes extra starches.
Once all the potatoes are cut, allow them to soak in the ice water for at least two hours. If you can, refrigerate them overnight. The cold water helps ensure your fries will be crispy.
When you’re ready to fry, heat a large 6 to 8-quart saucepot over medium heat and attach a cooking thermometer. Pour in the peanut oil or canola oil until it’s about 2 inches deep. Heat the oil to 350°F.
While the oil heats, take several handfuls of the soaked fries and dry them thoroughly using paper towels. This step is crucial, as excess moisture will cause the oil to bubble up dangerously.
Once the oil reaches the desired temperature, carefully lower a small batch of the dried fries into the hot oil using a skimmer. Be cautious, as moisture can cause the oil to splatter.
Fry the shoestring fries for about 2 to 4 minutes, stirring once to ensure even cooking. You’re looking for a medium blonde to straw color—this is when they’re perfectly crispy!
Use the skimmer to remove the fries from the oil and transfer them to a prepared pan lined with paper towels. Immediately sprinkle them with salt and pepper to season while they’re hot.
Repeat the frying process in batches, ensuring each batch is dried well before frying. You can keep the fries warm in a low 200°F oven, but keep in mind they may harden over time.