I am fairly new at this cake thing...and I am making a banana cake with a vanilla pastry cream filling. I want to add a layer of chocolate ganache under the pastry cream, but I'm afraid it will cause the pastry cream to not set up, or something else very bad and ruin my whole cake.

Do you know if this is okay?

I really want a chocolate flavor somewhere in the cake. Any other ideas if this won't work? I am using a merengue buttercream to frost since that's what I know how to work with and have been successful with.

Why not torte it so you have two layers of ganache and a layer of pastry cream in the center?

Exactly as Kitagirl said.

Mmmm, banana cake, ganache, banana cake, pastry cream, banana cake, ganache, banana cake. Would make for a lovely presentation too.

Thank you so much for the idea! I think I'm going to try it. I'm baking my cake in a sheet pan because I'm making a number one cake for my son's first birthday. You think I can cut three layers out of a sheet cake?

Well, that depends on how tall of a sheet cake you are baking and how thin you are cutting your cake layers.

I've done what you are thinking of when I did my boston cream pie type cake. I put the layer of ganache down first and then put my pastry cream on top and then put my next layer of cake. Worked just fine.

I have a Wilton sheet cake pan 12 X 18 X 2. Could I get three layers out of a two inch deep pan? I could do two layers of filling--one ganache and one pastry cream. Could I do two 1/2" layers and one 1" layer?

kyhendry--did you let the ganache set up first before adding the pastry cream?