Over medium heat, mix together the cream, half-and-half and salt in a medium saucepan until hot and steamy, but not simmering (about 5 minutes).

Place the egg yolks in a medium mixing bowl and whisk until combined.

Pour half of the warm milk mixture into the yolks in a slow and steady stream, whisking constantly.

Pour the mixture back into the saucepan and heat over medium heat, stirring constantly, until the mixture is thick enough to coat the back of a spoon. If using a candy thermometer, the mixture should reach 170°F (77°C).

Remove from the heat and stir in the vanilla and maple syrup.

If the mixture has any bits of egg yolk clumps (which mine didn't), strain the mixture through a fine-mesh sieve or a food mill set over a storage container. Let the ice cream cool completely, about 1 hour, and then refrigerate for at least 2 hours (preferably overnight) before churning according to your ice cream maker’s instructions.

Serve immediately for soft serve ice cream. For firmer ice cream, place the ice cream in a freezer-safe airtight container. Press a piece of plastic wrap against the ice cream (to prevent ice crystals from forming). Freeze for 2 to 3 hours or until firm. After 4 to 5 hours, it will become quite hard and not very easy to scoop. Let sit at room temperature for 10 to 15 minutes or until easier to scoop. Freeze for up to 2 weeks.