Step 1Wash the potatoes, wipe them dry and peel them (do not wash after peeling, but wipe them off with a dry cloth if necessary). Using a box grater, grate the potatoes coarsely. Place them in a bowl with the egg, salt and pepper and mix well. All this should be done just before cooking them.
Step 2Heat 2 tablespoons of the oil in a 12-inch frying pan (preferably cast-iron). When it is very hot, add all the grated potatoes and spread them out with the prongs of a fork, pressing down on them lightly to make a large crepe, or pancake, of even thickness. Cook over medium-high heat for 6 to 8 minutes, or until the underside has browned, then slide the crepe out onto a large plate.
Step 3Place the remaining oil in the pan, then place a second plate on top of the crepe and turn it upside down. Lift off the first plate and slide the crepe back into the pan to finish cooking 6 to 8 minutes on the second side. Serve immediately.