I am making a wedding cake at the end of the week and I was wondering if you can put MMF on a cake with canned icing that doesnt crust. Does it matter if it crusts if you are putting fondant over it?
All I can say is that canned icing isn't going to behave well for you.. it's gloppy and runny. You'd be better offmaking your own icing. You can do it for nearly the same cost of buying it in the can and it's behave (and taste) much better for you.
You'd have to chill it otherwise and I'd be afraid it might get really runny while thawing out.
I use the decorator's buttercream recipe from Wilton, with just a slight modification, and it works fine under fondant. I only ever use canned frosting for filling in a pinch. I've tried it for borders and roses when I was strapped for time, and it does not hold up at all.
It is best that you have a crust.....I had done a few with wet frosting when I first started and it just doesn't smooth out right and you get slippage and the icing would move around when you were trying to smooth the fondant and would ooz out the bottom.......Not a pretty picture....lol
I would take the time and make a good frosting that will set, there are a lot of BC icing recipes on this site and are not too difficult to do (and will taste a whole lot better)...Remember that you do taste that crumb coat..so you want it good.
I would say as long as you stiffened up the icing for a dam before putting the icing between the layers then allowed it to settle(overnight, if possible) with a thin coat(to help retain moistness of cake)of icing on the outside. Then, in the morning smear another thin, smooth coat of icing on it, there shouldn't be a problem. If you apply it thinly, the cake will absorb most if not all of the wetness from the icing which should keep the fondant from doing a slippy slide routine on the cake. I'd say yes you can do it with canned icing.
I only use non-crusting icing. Just pop it into the freezer to set it up before you put the fondnat on. Not a problem.
non crusting is fine... but i still don't know about the canned stuff. I would say crusting, non-crusting, and canned alike: put it in the fridge or freezer and cover the cake when icing is firm.
What leahs said... I use meringue based icing exclusively. Set it up in the refrigerator before covering with fondant and it works fine.
Oh, and I would never ever use canned icing. You can make icing in a snap.