In a saucepan, combine the heavy cream, whole milk, sugar, cocoa powder, and salt. Heat over medium heat, whisking continuously until the mixture is smooth and the sugar is dissolved.

Remove from heat and stir in the vanilla extract. Let the mixture cool to room temperature.

Once cooled, refrigerate the mixture for at least 2 hours or until thoroughly chilled.

Pour the chilled mixture into an ice cream maker and churn according to the manufacturer's instructions until it reaches a soft-serve consistency.

Transfer the ice cream to an airtight container. If desired, fold in chocolate chips. Freeze for at least 4 hours or until firm.