I need a good carrot cake recipe to feed 25 people. I'm planning on making a 9x13 or 2-layer 9 inch. Anybody got one that will for sure feed 25 or should i just make 2 recipes?

Here are all the CC recipes for carrot cake:

http://tinyurl.com/2x24k8

Wilton recommends 7 cups of batter per 13x9x2 pan for 45 party servings, and 5 1/2 cups per 9" pan for 24 party servings.

Here are the charts for your future reference:

http://www.wilton.com/cake/cakeprep/baking/times/index.cfm

Depending on what recipe you make, your batter yield will differ.

Doctored Carrot Cake Mix:

http://forum.cakecentral.com/cake-decorating-ftopict-42115-.html

HTH