I'm stacking two 13X9 red velvets and wonder if it's really necessary to support (board, dowel etc)? Will it sink? It's going to be a present cake.
When you say two 13x9s do you mean two 2in tall 13x9s? If so then no. Genaral you need support and a separate board when you are stacking over 4in.
Thanks! Yes, they're less than 4 inches. That's a good rule of thumb to know.... appreciate the info!