To peel a plantain, hold it under hot running water for one minute, then cut off both ends. Cut a slit down one side of the peel, and remove it. Slice flesh using a mandoline or a sharp knife.
Heat 4 inches oil in a heavy-bottomed saucepan over medium-high heat until it registers 360 degrees on a deep-fry thermometer. Working in batches of several strips, fry until golden brown, 2 to 3 minutes. Transfer to paper towels using a slotted spoon; let drain. Season with salt.