for a 12"x18"x 2" pan? I've only made this cake before in rounds.

One batch according to the recipe makes one 12" x 18" x 2", and you may even have some left over. You may not, depends on how full you want to fill up your pan.
Hope this helps. Happy Turkey!

http://www.recipezaar.com/White-Almond-Sour-Cream-Wedding-Cake-69630

That has all the pan sizes that one recipe will make.

Oh man, I had completely forgotten that the information was with the recipe...mine is hand written on a sheet of paper with lots of little notes around...and none related to pan sizes...I will definitely add it now...Thanks so much, and Happy Thanksgiving to you both!

One way to find out how much batter you need is to measure the pan with water. If you know how much batter/water you need to make the rounds then you can figure it out from there. Also I've read where some folks here mark on the bottom of all the pans the amount of cups it holds for so you don't have to re-measure or look it up (this is something I still have to do myself )

HTH!

Using DH white cake mix, a full recipe of the WASC cake yields a tad over 14 cups of batter.

Wilton party & wedding serving and cake preparation charts:

(2" pans)

http://tinyurl.com/5pbw7t

http://tinyurl.com/5pu7y9

(3" pans)

http://tinyurl.com/6642yq

http://tinyurl.com/5tgoob

Fat Daddio:
(For pan sizes not found above.)

http://tinyurl.com/4pc8a5

HTH

Thank you so much!