Place eggs in top of a double boiler; beat at medium speed of electric mixer until frothy. Combine sugar and salt; gradually add to eggs, beating until thick.
Bring water to a boil in bottom of a double boiler. Gradually pour milk into egg mixture, stirring constantly. Reduce heat to low; cook custard over boiling water, stirring occasionally, 20 minutes or until mixture thickens and coats a metal spoon. Stir in vanilla. Pour into serving bowls, and chill thoroughly. Garnish each serving with a dollop of whipped cream.