In a medium saucepan, combine the heavy cream, whole milk, brown sugar, ground cinnamon, and a pinch of salt over medium heat. Stir continuously until hot and sugar dissolves, about 5 minutes.

While the cream mixture heats, whisk egg yolks in a separate bowl until smooth and slightly pale, about 1-2 minutes.

Gradually mix in 1 cup of the hot cream mixture into the whisked yolks while whisking continuously to temper the yolks.

Pour the tempered yolk mixture back into the saucepan with the remaining cream mix. Cook over medium-low heat, stirring, until thick enough to coat the back of a spoon, about 5-7 minutes.

Strain the custard through a fine mesh sieve into a clean bowl to remove any cooked egg bits.

Stir in the vanilla extract and allow the custard to cool to room temperature for about 30 minutes. Then, refrigerate for at least 4 hours or overnight.

Pour the chilled custard into an ice cream maker and churn according to manufacturer’s instructions until soft-serve consistency, about 20-30 minutes.

Transfer the churned ice cream to a freezer-safe container, smoothing the top, and freeze for several hours until firm, around 4 hours.