Wash the potatoes well, but leave the skins on. Slice them into 1/8-inch thin slices, using a mandolin or food processor. Rinse the potatoes under cold water until the water runs clear and then let them soak in a bowl of cold water for at least 10 minutes. Drain and dry the potato slices really well in a single layer on a clean kitchen towel.

Pre-heat the air fryer to 300ºF. Spray the potato chips with the oil so that both sides are evenly coated, or rub the slices between your hands with some oil if you don’t have a spray bottle.

Air-fry in two batches at 300ºF for 15 to 20 minutes, shaking the basket a few times during the cooking process to move the chips around so they cook more evenly. Season the finished chips with sea salt and freshly ground black pepper while they are still hot.

While the chips are air-frying, make the sour cream and onion dip by mixing together the sour cream, olive oil, scallions, salt, pepper and lemon juice. Serve the chips warm or room temperature along with the dip.