1 1/2 cups heavy cream
In a medium bowl, blend lime zest, sugar, egg yolks, vanilla extract and salt. Set aside.
In a medium saucepan, heat the cream and milk together over medium heat until hot but not boiling. Slowly pour the hot cream-milk mixture into the zest-sugar-egg mixture to temper the eggs. Whisk away! Keep pouring in the hot cream-milk until completely blended. Whisk together well.
Return the entire cream-egg blend back into the saucepan and heat again over medium-low heat, stirring frequently, until the mixture thickens and the custard coats the back of a wooden spoon. Then, pour through a fine mesh sieve into a clean bowl and allow to cool slightly. Whisk the lime juice into the cooler custard, cover and chill until cold or overnight.
When totally cooled, whisk the custard once more and pour into an ice cream maker. Freeze according to the directions and store in freezer until hard. This ice cream is delicious served with blackberries or strawberries or would even be tasty with chopped kiwis. So refreshing!