Makesabout 8 cups
- Active time:15 min
- Start to finish:25 min
purple potatoes such as Purple Majesty or All Blue (see cooks' note, below)
vegetable oil for deep-frying
Cut potatoes into very thin (1/16-inch-thick) slices with slicer. Rinse slices in a large bowl, agitating them, then drain in a colander. Spread slices out in 1 layer on a clean kitchen towel and pat very dry.
Heat 2 inches oil in a wide 7- to 8-quart heavy pot over moderately high heat until thermometer registers 350ºF. Carefully add one third of potatoes, separating slices, and fry, stirring frequently, until chips are crisp, 3 to 5 minutes. Transfer chips with a skimmer to paper towels to drain and season with salt. Fry remaining potatoes in 2 batches. (Return oil to 350ºF between batches.)
Cooks' note: Purple potatoes are available at specialty foods shops, farmers markets, and from Culinary Specialty Produce (908-789-4700). We prefer Purple Majesty potatoes for this recipe because they result in a crisper chip.