My icing is melting off my cake! It is also causing my cake to sweat? It looks like brownish colored water coming off the cake! What do I do? I made a buttercream with butter and milk. At one point I put it in the freezer to harden up...was that a big mistake??
You may need to use more ps and less milk.
Agree it sounds too thin. Also, what is your fat/sugar ratio? Crusting is a result of fat/sugar ... more sugar, more crusting. More fat, less crusting.
But while I might put a cake in the freezer for 5 minutes when I'm rushed and need the crumb coat to set up faster, remember that anything frozen will melt when placed back in a room temperature environment. That's why I air dry my roses, flowers, and my icing in general.
If you read any thread on FBCT's, you will find consistent advice on "work fast ... once you take it out of the freezer, it starts to melt". Whether it's icing shaped like a rose, icing in a FBCT or icing on a cake, it's all icing and will react the same way to temperature change.
The only times I've ever had icing problems is when I put the cake in the refrigerator ... which is why I dont' refrigerate my cakes at all anymore.