Using a mandolin or very sharp, heavy knife, slice the potatoes into rounds as thin as possible, and place in a large bowl of water to prevent discoloration.
Heat the oil in a large, heavy pot to between 340 and 350 degrees F.
Pat the potatoes completely dry. Add to the oil in batches and cook until golden brown, stirring with a long handled spoon to turn and cook evenly, about 2 minutes. Drain on paper towels and place in a large bowl. Toss with the cheese, truffle oil, salt, and pepper. Serve immediately.
Yield: 4 servings