Pour 2 cups of fresh apple cider into a medium-sized pot, heat until it boils, then simmer until reduced to ¼ cup, about 30-45 minutes.

Stir in ¼ cup of melted unsalted butter, 1 cup of brown or muscovado sugar, a pinch of fine sea salt, and 1 teaspoon of ground cinnamon into the reduced cider, bringing it to a gentle boil for 2-3 minutes.

Whisk in 2 cups of heavy cream and 1 cup of whole milk into the cooled caramel mixture until smooth.

Cool the mixture to room temperature, then refrigerate for at least 6 hours or overnight.

Pour the chilled mixture into an ice cream maker and churn according to the manufacturer's instructions, about 20-25 minutes.

If desired, drizzle in melted caramelized white chocolate during the last few minutes of churning.

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