Ok, I'm having some trouble and don't know how to fix it. I always cover my cakes with fondant; therefore Ive never even gotten close to icing a cake well. Next week a friend's girls are turning 1 and she wants a regular iced cake.
My problem is, when I try to ice the cake with buttercream it rolls off the cake and almost always takes chunks of the cake with the icing. Ive also found that this happens when I try to ice a layer that doesnt have the crusted side of the cake on top (if I torte it and the baked side isnt on top). I wanted to attempt a topsy turvy cake, but know this will be an issue. Im sure its hard to tell me what Im doing wrong without being there, but does anyone have any tips?
Here's a great recipe I use all the time...
1 stick butter, softened
1 1/2 cup shortening (Crisco)
2 lbs powdered sugar
3 Tbsp.cornstarch
1/4 cup water
2 Tbsp Vanilla
1/4 tsp. almond extract
Combine butter & shortening until creamy. Add extracts. Slowly add powdered sugar, cornstarch & water. Set mixer to medium and beat for 8 minutes.
This is a great crusting BC!
Also try using the large icing tip (#789) to apply the icing before spreading it. Here's a video that explains it:
http://www.wonderhowto.com/how-to-ice-large-sections-cake-with-wilton-decorating-tip-789-393012/
Also, I find it's a lot easier if the cake is chilled to spread the icing without taking out chunks of cake.
Another tip (after you have thinned out your icing a bit) is to do a crumb coat (think layer of icing all over the cake, doesnt matter if there are crumbs visible), and then put the cake in the fridge until the icing has hardened completely. Then ice it again and you wont have to worry about crumbs. This works best if you have at least half butter in your icing. I find a shortening only icing never gets hard enough in the fridge.
Another tip (after you have thinned out your icing a bit) is to do a crumb coat (think layer of icing all over the cake, doesnt matter if there are crumbs visible), and then put the cake in the fridge until the icing has hardened completely. Then ice it again and you wont have to worry about crumbs. This works best if you have at least half butter in your icing. I find a shortening only icing never gets hard enough in the fridge.
Yes!! Creamy icing + crumb coat + chilling = easier time with icing. I actually put my crumb-coated cakes in the freezer for 30 min. or so before applying the final layer of icing.
I disagree about softening your icing!! Your icing should be super-duper thick. The thicker the better... not all anything close to whipped cream.
Your only problem is that you need to crumbcoat your cakes first. Do a nice crumbcoat and stick in the fridge for a while (I usually leave it overnight).
THEN and only then you can ice your cake and you will find that your icing won't peel off.
Good luck. 
To tell if your icing is too thick - if you use the large icing tip and you cannot squeeze it out - start again and add more water or milk. (Depends on what recipe you are using)
Always have the crumb coat in place. I dont place in the frig - but do let the cake rest for about 20 minutes.
Good luck
when I try to ice the cake with buttercream it rolls off the cake and almost always takes chunks of the cake with the icing.
I agree with everyone that gave the good advice to thin your icing to a more creamy consistency. If it isn't creamy and spreadableit will pull up crumbs, take off chunks of cake, and won't stick to the cake if it's too thick and dry.
I disagree with Mug-a-Bug's advice to make "super-duper thick" icing, and "the thicker the better", and I take offense to the comment that "THEN and only then" is it possible to ice a cake.
Mug-a-Bug: There are a lot of experienced decorator's that have been icing cakes with creamy icing for many years without considering stiffening it up, and they do just fine. (Including professionals who can ice without a crumb coat.) Maybe stiff icing works for you (and that's great), but your way isn't the only way as stated in your post. I'm sure many would agree "the thicker the better" would mostly apply to mixing rose icing. (If your post was a jokeI fell for it!)
when I try to ice the cake with buttercream it rolls off the cake and almost always takes chunks of the cake with the icing.
I agree with everyone that gave the good advice to thin your icing to a more creamy consistency. If it isn't creamy and spreadableit will pull up crumbs, take off chunks of cake, and won't stick to the cake if it's too thick and dry.
I disagree with Mug-a-Bug's advice to make "super-duper thick" icing, and "the thicker the better", and I take offense to the comment that "THEN and only then" is it possible to ice a cake.
Mug-a-Bug: There are a lot of experienced decorator's that have been icing cakes with creamy icing for many years without considering stiffening it up, and they do just fine. (Including professionals who can ice without a crumb coat.) Maybe stiff icing works for you (and that's great), but your way isn't the only way as stated in your post. I'm sure many would agree "the thicker the better" would mostly apply to mixing rose icing. (If your post was a jokeI fell for it!)
Snippy 
Just my opinion, take offense if you want, but it's what works for me, and my buttercream is ammmmaaazing! 
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