Creamy Lemon Custard Ice Cream

Bring the cream, half and half, sugar and zest just to a boil over medium heat in a heavy medium saucepan, stirring to dissolve the sugar.

Whisk the egg yolks and salt together in a medium bowl. Add 1/2 cup of the cream mixture to the yolk mixture and whisk until blended.

In a slow, steady stream, add the remaining cream mixture, whisking constantly, and continue whisking until blended. Return the mixture to the saucepan and cook, stirring, over medium-low heat until the custard thickens and leaves a path on the back of a wooden spoon when a finger is drawn across it; do not allow the mixture to boil.

Immediately pour the custard through a strainer into a bowl and stir in the vanilla.

Let cool to room temperature, whisking occasionally.