In a saucepan combine the sugar, salt, cocoa powder. Whisk thoroughly so that there are no clumps of cocoa powder. While whisking, slowly add the milk and half and half. Turn the heat to medium-low. Stir constantly and bring to a simmer. (Just when bubbles form on the sides of the pan.) Remove from heat.
Place the beaten egg yolks in a small bowl. Gradually stir in ½ cup of the hot liquid to the egg yolks. Slowly drizzle the egg yolks back into the saucepan, stirring constantly.
Place saucepan over low heat. Heat until thickened (it should coat the back of a spoon), but DO NOT BOIL. When using an instant read thermometer mine was 180°F.
Remove from heat. Stir in the finely chopped chocolate until the chocolate has completely melted.
Pour the chocolate mixture through a sieve into a large bowl. *
Place the large bowl full of the chocolate mixture on top of an ice bath. ** Stir every 2 minutes. After 10 minutes place in the fridge for 2 hours or until cold.
Remove chocolate mixture from fridge. Stir in the cream and vanilla. Pour into an ice cream maker and freeze according to manufacturers directions.
Place in a bread pan, garnish as desired, cover, and freeze for 3-4 hours if you prefer a firm ice cream consistency.