Put the flour and salt in a bowl and make a well in the center of the flour. Pour the egg and some of the milk into the well. Whisk the egg and milk, gradually incorporating the flour to make a smooth paste. Whisk in the remaining milk, then pour the batter into a cup with a pour spout. Batter may be set aside at this point to rest if needed.
Place a little butter or oil in a crepe pan or heavy bottomed skillet and heat until the butter begins to smoke. Pour off any excess fat, and pour a little batter into the pan, tilting the pan to coat the bottom with a thin layer of the batter. Cook 1-2 minutes until the underside of the crepe begins to turn golden brown.
Flip the crepe with a spatula, and cook 30-45 seconds more, or until the second side is golden brown as well. Slide the crepe out of the pan. Continue cooking crepes in this manner, greasing the pan as necessary, until all batter is used.