I have been searching for a rootbeer flavor cake and love the WASC cakes. Would i just take the liquid and replace it with rootbeer?
Another option is "Root Beer Extract". I have purchased it at WalMart, near the other cooking extracts. I know that the cupcake bakery uses it for their rootbeer cupcakes.
I would go with a rootbeer extract as well...in addition, you could research what kind of spices you could add that have that rootbeer flavor. I think the problem with replacing the water in a WASC recipe with rootbeer is the added sugar in the rootbeer will make the cake way too sweet...but perhaps you could compensate for that by adding less sugar.
I'm sure if you look around on the web for a while, you could find some good Coke cake recipes- they are common enough, try experimenting with those replacing the coke with rootbeer. Good luck and let us know if you stumble across an amazing new cake in the process!
This is a Paula Dean doctored box mix recipe that might suit you. I found this while I was look for the scratch recipe.
The recipe is in here:
I have one in the oven now. It takes a dram of Lorann rootbeer, actual rootbeer, and yogurt (but you can sub sour cream for the yogurt).