Place half-and-half in a medium saucepan. Split vanilla bean and scrape the insides into the half-and-half and add vanilla pod. Place over medium heat until quite hot and steamy, but not boiling. Remove pod and remove pan from heat.

In a medium bowl, whisk together egg yolks and sugar until pale yellow, about 2 minutes.

While whisking continuously, and, starting very slowly, then increasing in volume, add hot half-and-half to the egg yolk mixture.

Place mixture back in saucepan over medium heat, and, whisking continuously, cook until thickened, about 5 minutes. Remove from heat.

Pour custard into a bowl, stir in heavy cream, vanilla, and salt. Refrigerate until completely cooled, about 8 hours.

Churn according to the instructions on your ice cream maker.