Please HELP with my chocolate ganache.

Can you carefully scrape it off?

If the chocolate didn't all melt, that would explain why it didn't set up properly.  I would try heating it in the microwave slowly and using a whisk to completely mix the chocolate into the cream. 

http://www.youtube.com/watch?v=TD9InBb6i34

After you get all the chocolate melted and incorporated into the cream, you can hurry the cooling process by putting it in the fridge and stirring it every 5 - 10  minutes til it's the right consistency.  Shouldn't take too long.  You can add ganache to buttercream, but it makes chocolate buttercream  - a totally different thing that is delicious but NOTHING like ganache. 

Equal partake chocolate and cream, like is your recipe make a pouring ganache, not a spreadable ganache.

"Classic ganache frosting usually has equal weights of chocolate and cream.  Since I find this consistency is just a shade too stiff to adhere well to cakes, I have very slightly increased the amount of cream so that the frosting is fudgy and thick while still able to cling to the cake."  Direct quote from The Cake Bible, Rose Levy Beranbaum

 

The recipe I use is from this book.  The longer it sets (cools) the stiffer it gets. 

Huh. I usually do 1.5 parts chocolate to one part cream. Oh well.

I use two parts chocolate to cream and in the heat we've had here in the last couple of days, even that didn't set up enough. Ganache depends a lot on the weather.

 

Oops- came back to say, you can add more chocolate, OP. Just heat it up again and stir through whatever amount of melted chocolate you think is enough. Probably the same amount you have already put in. Ganache used for spreading should come to a spreading consistency at room temp overnight - in the fridge it goes rock hard.

http://www.youtube.com/watch?v=qFtm8q4m4Bk

 

I use these ratios all the time. It works great!!

Just made a ton of ganache Heat the cream till its slightly hot, add choc chips or chopped choc...equal ratios. Let it sit for 5 mins then mix with a whisk.

If the choc isn't melted yet, microwave it at 20 sec intervals until the whisk is able to incorporate it all well. Let it sit out overnight and it should harden to a spreadable consistency.

I read that you shouldn't refrigerate it because the variance in temps as it comes back to room temp can cause it lose the thick consistency.

Also, if it's grainy, just warm it a bit, whisk then add a little cream if needed. It should repair itself that way.

i also find it depends on the weather. Have had to up my chocolate ratio massively with the heat we have been having lately. Also, to avoid grainy ganache, I find using a metal whisk does the trick. Not sure why it works so much better, perhaps because the whisk heats up too and melts the chocolate as it contacts it? (I make my ganache on the stove top =))  and dont be scared to reheat ganache.. its one of the beauties of it.. it wont hurt it to reheat it.