Add 1 cup of heavy whipping cream to a large bowl. Set aside.
Add the egg yolks to a medium bowl and whisk together. Set a fine strainer beside it. Set aside.
Combine sugar and lemon zest to a medium sized saucepan. Rub the zest into the sugar with your hands.
Add the remaining 1 cup of heavy whipping cream to the saucepan along with the milk and salt. Mix together and place the saucepan over medium heat.
When the milk mixture is hot, but not boiling, slowly ladle an amount into the egg yolks, whisking continuously to temper the eggs.
Pour the tempered eggs into the saucepan, and whisk constantly over medium heat. The mixture will be ready when it has thickened and coats the back of a spoon, or the temperature reaches 170°F.
Immediately strain the custard into the large bowl with the heavy cream in it, and stir. Let the custard cool to room temperature, about 30 minutes. Cover and refrigerate until ready to churn, 4 hours or overnight.
When you are ready to churn the ice cream, stir in the vanilla extract and lemon juice to the cooled custard base. Transfer the ice cream to an ice cream maker and churn according to the manufacture's instructions.
Store the ice cream in an airtight container and place it into the freezer until it is ice cream consistency, about 6 hours.