I'm sure if I search this site I can find the answer to this question, but I'm basically lazy, so I'm calling on all of the cakers out there who love the internet. I'm just starting out in this business...been home baking for many many years, and have a stable of great recipes that I use.
I've got an order for a birthday cake to serve 15. Was planing on using 9" round cake pans, 2" high. Is a two layer cake with buttercream frosting going to be enough? (I usually say that this cake servers 12-14) but do I really need to do another whole layer to serve 1 more person?
It is going to be the only dessert. I'm using a Rose Levy Beranbaum recipe, and it says it serves 12. They are big pieces...but since you are so shocked by the size...I'm going to say that it is going to be enough cake...LOL. Thanks so much for your input.
A 9" round cake will be enough for 15. It will not serve 30 to a birthday party ...that's wedding sized servings. But you will still have more than you need. I think it will serve around 20 for party sized servings. And that's good size pieces! 
I just made a cake for 15 this past weekend... but they are big people with big appetites so I made them a 10" square knowing that they think a 3" square is a serving. Quote by @%username% on %date%
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