Preparation -
In a sauce pan, combine sugar, flour, salt, and milk. Cook and stir over medium heat until mixture begins to boil. Reduce heat to medium low and cook, stirring constantly, for 2 1/2 to 3 minutes. Remove from heat for a few minutes; stir 1/2 cup of hot pudding mixture into beaten egg yolks. Pour this into hot pudding mixture in saucepan; return to heat and cook over low heat for 2 to 3 minutes, stirring constantly. Remove from heat; stir in vanilla. Tastes best if chilled before serving.
Optional - Sprinkle lightly with cinnamon before serving. .