Place the milk in a medium saucepan. Heat over medium-low it just begins to simmer.

While the milk is heating, whisk together the salt, sugar, and egg yolks in a medium bowl. Gradually pour the hot milk into the egg yolks; whisking vigorously the entire time.

Return the mixture to the saucepan and cook over medium-low heat, stirring constantly, until the mixture thickens and coats a wooden spoon. (~6-7 minutes)

Remove mixture from heat and add the heavy cream; stir until well combined. Pour the mixture through a fine-mesh strainer into a clean container. Stir in the bourbon (optional), vanilla, nutmeg, and cinnamon. Cover with plastic wrap, pressing the plastic directly onto the surface of the mixture, and refrigerate overnight.

Pour the ice cream mixture into an ice cream maker and freeze according to the manufacturer's directions.

If you desire a firmer ice cream, transfer the finished ice cream into the freezer for a couple of hours.

Garnish with a dash of cinnamon and freshly-grated nutmeg before serving.