Combine the sugar, flour and salt in a sauce pan. Slowly stir in hot milk. Cook over low heat for about 10 minutes, stirring constantly until mixture has thickened. Mix a small amount of hot mixture into eggs. Add eggs to hot mixture and cook a minute longer. Chill mixture in the refrigerator. Add cream and vanilla. Pour into 1 gallon ice cream freezer and prepare as normal. Makes four quarts, supposedly enough for 12 - 16 people.