1 vanilla bean, split lengthwise, seeds scraped out
10 large egg yolks
1 cup sugar
Pinch of kosher salt
Combine the heavy cream, milk, and vanilla pod and seeds in a large saucepan. Bring to a gentle simmer over medium-high heat, then remove from the heat.
Whisk the egg yolks, sugar and salt in a medium bowl. Ladle half of the cream mixture into the egg mixture and whisk to combine; return to the saucepan with the remaining cream mixture. Cook over medium heat, stirring constantly with a wooden spoon in a figure-8 motion, until the custard is thick enough to coat the back of the spoon, about 10 minutes.
Strain the custard through a fine-mesh sieve into a blender; discard the vanilla pod. Puree until frothy, about 30 seconds; pour back into the bowl. Cover with plastic wrap and refrigerate at least 3 hours or overnight.
Transfer the chilled custard to an ice cream maker and churn according to the manufacturer's instructions. Transfer to a resealable container and freeze until firm, about 2 hours.