Please help. Why when I cover a cake in fondant, why does it 'pool' or bulge out on the bottom after sitting for a while?

I'm not sure about your particular situation/type of bc you are using so perhaps you can share details?

Sometimes this can happen because the cake hasn't had time to settle or you don't have a thick dam keeping your fillings in before putting the fondant on and the weight of the fondant is pulling down. It can also happen if you have butter in your buttercream and it is warm, or if you have too much bc in your undercoat and too thick of a layer of fondant. Someone once told me on here that if you use a thick coat of fondant (1/4" or more) you should just use a crumb coat of bc, if you use a thin layer of fondant (1/8"-3/16") you can use a thicker crumbcoat. This has held true for me.

I was going to ask a similar question. My fondant covered cakes look like they are melting, for lack of a better description. The fondant ends up shiny all over and saggy at the bottom of the cake. At first I thought it was due to the buttercream melting or sliding, but then why would the fondant be shiny all over. This has happened to cakes that I stored in my wilton carrier, at room temperature (77%), not in direct sunlight. Is the temperature too warm? Should a fondant covered cake not be stored in an airtight container? Or am I doing something else wrong? I roll my fondant fairly thin, so I don't think that is the issue.

Usually this is due to your cake settling after the fondant has been applied. The fondant is the right size when your cake is 4.25 inches tall but when it settles down to 4 inches then you will have a quarter inch of fondant that is now extra and puddling down the side of your cake. I fill and crumbcoat my cake and let it settle for at least 2 hours, more if I have the time, before I cover it with fondant. And, yes, the thickness of the fondant is a factor too..too thick and it can stretch due to gravity, too thin and you see the cake thru the covering so you have to find your happy medium. Mine is about the thickness of a nickel. That's what works for me for a smooth finish. HTH. Cat

A fondant covered cake should NEVER be stored in an air tight container at room temp. The moisture from the cake collects in the container (shiny surface) and the fondant softens (pooling/melting/schlumping).

Best to keep a freshly covered cake (if it doesn't require refrigeration) at room temp in a cardboard box out of direct heat & light.

The only time I leave a fondant covered cake wrapped up is on the rare instance when it's defrosting in a fridge and then coming to room temp on the counter (so no condensation forms). Once it's at room temp, I take it out of the covering immediately.

Rae

Ahhh.... that explains my problems. I'm not sure if that is what is happening for the OP or not. I have to use something to protect the cake from the cats... and a cardboard box just calls to them whether there is cake inside or not. I'll have to find something else to use.