Place slices in a bowl of cold water and add the vinegar. You should notice the water become cloudy as surface starch loosens. Soak for 15 to 20 minutes to remove excess starch that would otherwise cause sogginess.

Rinse the slices under cold running water until the water runs clear. Pat thoroughly dry with clean kitchen towels or paper towels. Moisture is the enemy of crispness, so be meticulous here.

Heat oil in a heavy pot to 175 degrees C (350 degrees F). I use a thermometer to maintain precision. The oil should shimmer but not smoke.

Fry in small batches, 30 to 40 seconds per batch, without crowding. You'll see the edges bubble and the slice turn golden; the aroma becomes faintly nutty and sweet. A single chip will go from pale to golden in under a minute.

Remove chips with a spider and transfer to a wire rack or paper towels. While still hot, sprinkle with kosher salt or seasoning. The residual oil helps adhesion of the seasoning to the surface for immediate flavor.

Let chips cool completely before storing. They crisp further as they cool and firm up. If you taste one warm, you'll get the initial crunch but the final crisp is best after cooling 5 to 10 minutes.