I really hate making square cakes. Well, my sister is getting married in june and wants a square cake. I am dreading it!!!! I know many decorators use ganache under fondant. My problem is that everytime I have made ganache, it is very runny. I really have know idea how I would possibly "smooth" it. Am I using the wrong recipe? Any help would be greatly appreciated!!!! Also, I know that whipping cream makes fondant slimmy, so how does the fondant not turn to slime with the ganache? Hope that makes sense!
Your ganache should be a very thick peanut butter like consistency. To achieve this you have to use a 2:1 ratio of dark chocolate to cream or 3:1 for milk or white chocolate. So, for 60% cocoa, if you use 600g of chopped chocolate, you would use 300g of hot cream. Mix until smooth and shiny and then let it rest overnight until thick like peanut butter.
Once the ganache is on and smooth, you let the cake sit overnight or in the fridge for several hours and it becomes hard and forms a shell. Then you apply the fondant. I'm not sure what you mean by "slime" but I have never experienced this with ganache.