2.

Meanwhile, heat oil in a 5-quart Dutch oven or large wok over high heat to 400°F (204°C). Add one-third of fries to oil; oil temperature should drop to around 360°F (182°C). Cook for 50 seconds, agitating occasionally with a wire mesh spider, then remove to a second paper towel–lined rimmed baking sheet. Repeat with remaining potatoes (working in 2 more batches), allowing oil to return to 400°F after each addition. Allow potatoes to cool to room temperature, about 30 minutes. Continue with step 3, or, for best results, freeze potatoes at least overnight or up to 2 months.