In a medium-sized saucepan, whisk together the heavy cream, whole milk, sugar, vanilla extract, and sea salt. Place over medium-low heat and continue whisking frequently for about 5 minutes, or until the sugar has completely dissolved and the liquid is gently warmed.
Transfer the mixture into a heat-safe bowl, cover it, and place in the refrigerator for at least 2 hours, or let chill overnight for best results.
Once chilled, take the mixture from the fridge and whisk it again to ensure uniform consistency. Pour it into an ice cream maker and churn according to the machine’s specific instructions, typically taking 20 to 30 minutes. The resulting ice cream will have a soft, smooth texture.
For a firmer finish, move the churned ice cream into an airtight container and place it in the freezer for 2 to 4 hours.
Store any remaining ice cream in the freezer, sealed in an airtight container, for up to one month. Allow the ice cream to rest at room temperature for a few minutes if it becomes too hard to scoop.