Okay, from you I have "learned" lots of things but was just asked if I could do a "simple" wedding cake but with sugar free frosting. I've found some using cream cheese & whipped topping but sure would love other ideas! I'm not sure how I would get a smooth look on a cake with whip topping so if this is "the" go to recipe-advice on how to smooth is also appreciated....thanks in advance!

Chocolate ganache is chocolate and heavy cream. Some recipes will add butter too. Once it is set, it can be whipped into and has the consistency of frosting. If it is over whipped it will taste and look grainy.

There is a recipe on Allrecipes.com that has a high rating with feedback too.

Be sure you use sugar free chocolate.