Boil the Potatoes: Place potatoes and vinegar in a saucepan. Add 2 quarts water and 2 tablespoons salt. Bring to a boil over high heat. Cook for 10 minutes until tender but not falling apart. Drain and spread on a paper towel–lined baking sheet. Allow to dry for 5 minutes.

First Fry: Heat oil in a Dutch oven or wok to 400°F (204°C). Add one-third of the potatoes. Oil temperature should drop to 360°F. Fry for 50 seconds, stirring gently with a spider. Remove fries to another paper towel–lined tray. Repeat with remaining batches, letting oil return to 400°F each time. Allow potatoes to cool to room temperature, about 30 minutes. For best results, freeze overnight before continuing.

Second Fry: Return oil to 400°F. Fry half of the cooled potatoes until crisp and golden, about 3½ minutes, adjusting heat to maintain around 360°F. Drain on paper towels and season with kosher salt. Keep finished fries warm on a wire rack in a 200°F oven while you fry the second batch.

Serve Immediately: Dish out the hot fries and enjoy them fresh. They pair wonderfully with classic dips or as a side to hearty dishes like Boilermaker Tailgate Chili.