Just wondering your techniques for preventing the bubbling out of frosting/filling between layers.

After the cake settles there tends to be a slight protrusion through the frosting/fondant at the point where the layers meet. This isn't just one tiny air bubble, its like the frosting is almost seeping out around the entire middle of the cake. I dont put a ton of filling into my cakes either; this seems to happen whether I'm making a cassata cake or simply holding 2 rounds together with a small amount of buttercream.

Any recommendations?

http://cakecentral.com/cake-decorating-ftopict-633571-tile.html

Check out this thread.

You want to give your cakes time to settle before you ice and fondant them. This will help. Also when you do your dam or filling, don't go all the way to the edge of the cake, stay inside the edge. The weight of the cake will press it out some, so if you are already in, it will have less sticking out away from the sides of the cake.

It's been so hot where I am that all summer I've been making my dam out of cake ball stuff. (I'll bake and extra cake and follow a basic cake ball recipe, like Paula Dean's. And I freeze what's left over.) So far it's been helpful. You still have to let the cake settle like TexasSugar said. I don't use the tile method because I don't have the right tiles on hand and just haven't gotten them yet.

Most of the time the bulges come from over filling a cake and lack of letting the cake settle down.
Edna