In a medium saucepan over medium heat, combine 1 cup of the heavy cream, milk, sugar, and cinnamon, stirring until sugar is dissolved.

Remove from heat and stir in the remaining 1 cup of heavy cream and the vanilla extract.

Chill the mixture in the refrigerator for at least 2 hours or until very cold.

Pour the chilled mixture into an ice cream maker and churn according to the manufacturer's instructions.

Transfer the ice cream into an airtight container and freeze for at least 4 hours before serving.