I need to make a 1/2 sheet cake and forget how many batches of WASC I need. Is there something out there of how much batter is needed for certain sized pans? Thanks!

15 cups of batter.

http://www.wilton.com/cakes/making-cakes/baking-party-cake-2-inch-pans.cfm

I make the 2 box version of WASC for my 1/2 sheet. I am switching to Duncan Hines though, as it yields more batter. I do not get the desired height from Pillsbury.