Combine sugar, milk, salt, cocoa powder, cinnamon, and cream in a medium saucepan over medium heat, stirring very frequently until the mixture simmers but does NOT boil . Reduce the heat to low.
While the milk mixture is heating, lightly stir together the egg yolks in a small bowl.
When the milk mixture is simmering, remove 1/2 cup of the liquid and gradually add it to the egg mixture stirring constantly. When the mixture is smooth and combined, gradually add the egg mixture back to the milk mixture, stirring constantly. Continue to heat the mixture (but do not boil) until the mixture is thickened to a point where if you dip a wooden spoon into it and then trace your finger across the back of the spoon, it would leave a trail. Remove from heat.
Add the chopped AMERICAN HERITAGE® Chocolate Block. Stir until the chocolate is completely melted, then transfer the mixture to a metal or glass bowl, cover, and then chill for at least two hours.
When the mixture is completely chilled, stir in the vanilla. Freeze in a 2-quart (or smaller) ice cream freezer according to the ice cream manufacturer's directions. When the ice cream is almost done churning (about the consistency of soft serve), add the marshmallows and pecans and allow the ice cream maker to churn the ingredients into the ice cream, then transfer to freezer-safe containers leaving about 1/4-1/2" of headspace at the top to allow for expansion. Freezer for at least a few hours before serving (if you have a flash freeze feature on your freezer, that will help keep ice crystals to a minimum.)