Heat oven to 300 degrees F.
Whisk yolks, sugar and salt in bowl until thickened.
Heat half-and-half and milk in saucepan until small bubbles appear around edge. Scrape seeds from bean into milk mixture; add bean. Remove from heat and let stand 5 minutes.
Remove bean from saucepan; strain milk mixture. Pour into yolk mixture, stirring constantly. Stir in vanilla extract. Pour into six 5-ounce ramekins, dividing equally. Gently blot any foam from tops with paper toweling. Set ramekins in large shallow pan. Pour hot water into pan to depth of 1 inch.
Bake in 300 degree F oven 1 hour, until custards set. Remove from pan. Chill. Makes 6 servings.
