Combine the butter, cream, syrup, sugar, cocoa, vanilla extract, chocolate extract, cinnamon and salt in a medium saucepan over medium heat and bring to a simmer. Simmer on low, slowly whisking, for 3- 5 more minutes after it begins to simmer.
Turn off heat and stir in chopped chocolate or chocolate discs.
Whisk until completely melted and smooth.
Divide hot fudge among jars and tie on a label. Store in the refrigerator for a month or two.
