Using a mandoline or sharp knife, cut 1 medium russet potato crosswise into very thin slices (about 1/8th-inch thick). Transfer to a large bowl and add enough ice water to cover. Soak for 20 minutes.
Drain the potatoes well. Spread them out in a single layer on a double layer of paper towels to dry. Let dry for 10 minutes. Wipe the bowl dry.
Heat an air fryer to 370°F. Meanwhile, return the potato slices to the bowl. Add 1 tablespoon canola oil and 1/2 teaspoon kosher salt and toss until evenly combined.
Coat the air fryer basket with cooking spray. Add enough potato slices to sit in a single, even layer. Air fry until golden brown and crispy, shaking the basket or rotating the trays or flipping the chips every 4 minutes, 15 to 18 minutes total.
Carefully transfer the chips with a slotted spoon or tongs to a serving plate or bowl. Repeat air frying the remaining chips, patting them dry before air frying if needed. Season with more kosher salt while warm.