Preparation Bring large pot of salted water to boil. Line large baking sheet with several layers of paper towels. Cut 1 potato lengthwise into 1/4-inch-thick slices. Stack 2 to 3 potato slices at a time and cut lengthwise into 1/4-inch-wide sticks. Cook potato sticks in boiling water just until beginning to soften, 3 to 4 minutes. Using slotted spoon or tongs, transfer potato sticks to paper-towel-lined baking sheet to drain. Repeat cutting, blanching, and draining remaining potatoes. Pat potato sticks dry with additional paper towels. DO AHEAD: Can be made 4 hours ahead. Let stand uncovered at room temperature. Pour enough canola oil into heavy large pot to reach depth of 4 inches. Attach deep-fry thermometer to side of pot; heat oil to 350°F. Working in batches, add potato sticks to oil and fry until golden brown, about 6 minutes. Transfer to clean paper towels to drain. Sprinkle with salt and pepper. Serve immediately. TEST-KITCHEN TIP:For best results, serve each batch of fries immediately. If necessary, they can be kept warm on a rimmed baking sheet in a 300°F oven while the remaining potatoes are fried.