In a medium saucepan over medium heat, combine the half and half and vanilla extract.

Heat until the mixture just begins to simmer, then remove from the heat and set aside.

In a separate heavy-bottomed pan, combine the granulated sugar and ¼ cup water.

Heat over medium heat, stirring until the sugar dissolves.

Increase the heat and bring to a boil without stirring.

Cook for approximately 8 minutes until the syrup turns a deep golden amber.

Swirl the pan occasionally to ensure even caramelization.

Very slowly and carefully pour the warm half and half into the amber caramel.

The mixture will bubble vigorously and expand; continue whisking until the caramel is fully incorporated and the liquid is smooth.

In a ceramic bowl, whisk the egg yolks until uniform.

Slowly pour approximately ½ cup of the warm caramel-cream into the yolks, whisking constantly.

Immediately pour the yolk mixture back into the main pan.

This technical tempering prevents the eggs from scrambling.

Stir the mixture over medium heat for about 5 minutes until the custard thickens enough to coat the back of a spoon.

Pour into a glass bowl and refrigerate for at least 4 hours to stabilize the base.

Pour the chilled custard into the bowl of an ice cream maker and process according to the manufacturer's directions.

During the final two minutes of churning, incorporate the sea salt and chopped bittersweet chocolate.

Serve immediately for a soft-scoop texture, or freeze for a firmer finish.