I feel like I keep coming here with basic "duh-logic" questions, but I'm doing a wedding cake soon and want to get it right!
Is crusting buttercream what I want to use when I dirty ice before applying fondant?
Can I use crusting buttercream as a filler between layers? This seems like the easiest and safest thing to do for my first big cake (3 tiers)...
When you say "dirty ice" is that the same as crumb coat?
Yes you can use a crusting buttercream for a crumb coat/dirty ice and as a final coat and as a filling.
The only difference between a crusting and a non-crusting buttercream is that one forms a crust on the outside when it drys and one doesn't. People use a crusting buttercream when using the Viva method to smooth their cakes. HTH and good luck!
I use crusting buttercream almost all the time as my fillings. I don't have to worry about making an extra batch of anything and there's no need to refrigerate. Best of both worlds. =)