Put the flour and salt into a warm bowl. Cream the yeast and sugar, and add the beaten egg and warm milk. Add the liquid to the warm dry ingredients to make a thin batter, adding a little more warm milk if necessary. Cover the bowl and leave in a warm place for thirty minutes until double in size. Heat a griddle, hotplate or heavy frying pan and grease it lightly. Pour a small cupful of the yeast mixture on to the griddle. Cook one side, turn and cook the other side.