1. Heat the milk, salt, and sugar in a saucepan. Scrape the seeds from the vanilla bean into the milk with a paring knife, then add the bean pod to the milk. Cover, remove from heat, and infuse for one hour.
2. To make the ice cream, set up an ice bath by placing a 2-quart (2l) bowl in a larger bowl partially filled with ice and water. Set a strainer over the top of the smaller bowl and pour the cream into the bowl.
3. In a separate bowl, stir together the egg yolks. Rewarm the milk then gradually pour some of the milk into the yolks, whisking constantly as you pour. Scrape the warmed yolks and milk back into the saucepan.
4. Cook over low heat, stirring constantly and scraping the bottom with a heat-resistant spatula, until the custard thickens enough to coat the spatula.
5. Strain the custard into the heavy cream. Stir over the ice until cool, add the vanilla extract, then refrigerate to chill thoroughly. Preferably overnight.
6. Remove the vanilla bean and freeze the custard in your ice cream maker according to the manufacturer’s instructions.