I can’t usually get my hands on good unsweetened chocolate and usually it’s very expensive (Lindt at $3.00 for 50grams—ouch!) so I converted the Snowball Hot Fudge Sauce from RHC to use bittersweet chocolate (58%). I think the sauce is comparable to the original—maybe a hint sweeter but easily adjusted by reducing sugar. Texture seems much the same—a thick, sticky ganache…
I eliminated the use of unsweetened:
1. Increase chocolate by 3 oz.
2. Reduce butter by 1 oz.
3. I used 10 T of sugar, but may go slightly less next time ... I prefer a less sweet sauce…try 8 T?
Follow remainder of recipe as written. This is a great sauce—it does stiffen in the fridge and I just sampled some out of the freezer—very firm but easily scoopable with a spoon! I think it would be downright deadly swirled into homemade ice cream (just so it’s marbled, but not homogeneous—upcoming baking project!)