How to apply layout to AsyncAppender?

I have a scenario where I want to use multiple appenders for the same logger (FileAppender and SocketAppender for now). Both appenders need to format the message using the same layout. Instead of formatting the single message multiple times(in the FileAppender and in the SocketAppender), I was wanting to put both of these appenders under an AsyncAppender and apply the layout once in the AsyncAppender, then send the formatted message to my sub-appenders. What is the best way to accomplish this? From what I can tell the AsyncAppender does not support layouts.

Thanks,
Robbie