In a 4-quart saucepan over moderate heat, bring the cream, corn syrup, sugar, salt and chocolate to a boil, stirring constantly. Simmer until mixture thickens, about 5 minutes.
Remove from the heat and whisk in the butter. Serve while still warm.
What Makes This Recipe Sing: The versatility of this sauce makes it the WOW hostess gift. Try with grilled fruit, over sponge cakes or even as a "no need for the fondue pot" chocolate dunk for fresh fruits, cookies and pound cakes. This sauce is a classic and of course perfect for your favorite ice cream... My choice is peppermint ice cream. Also, it makes for easily made s'mores and if all else fails, just use a good old-fashioned spoon!
BYOC: Try adding a swirl, by heating peanut butter and swirling in the fudge. Add your favorite toasted nuts, a drop of peppermint or orange oil, or even your favorite cereal for a crunchy fudge sauce.