Creamy Lemon Custard Ice Cream

This isn't the best picture but this ice cream was SO delicious!

Makes about 1 1/2 quarts, uses about 6 lemons

2 cups heavy (whipping) cream
2 cups half-and-half
1 cup sugar
1/3 cup finely grated lemon zest
6 large egg yolks
pinch of salt
1 teaspoon pure vanilla extract
3/4 cup fresh lemon juice

1. 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.

2. 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.

3. Immediately pour the custard through a strainer into a bowl and stir in the vanilla.  Let cool to room temperature, whisking occasionally.  Refrigerate, covered, for 3 hours, until thoroughly chilled.

4. When ready to freeze, stir the lemon juice into the cold custard, pour the mixture into an ice-cream maker, and freeze according to the manufacturer's instructions.  The ice cream will be soft, but ready to eat.  For a firmer texture, transfer to a freezer container and freeze for at least 2 hours before serving.