I have to make a 14" square cake, 4" deep but I only have one 2" pan - can I collar my pan to bake up another two inches? (or even three inches would be fine, just as much higher as I can!) If I can, how?

Here's a CC article on collaring (round) cake pans:

http://cakecentral.com/articles/101

The deeper the cake pan, the longer and slower the cake layer must be baked. I find it easier and faster just to bake two 2" layers to equal the traditional 4" layer cake.

Quite a few members (myself included) have 3" pans, but prefer our 2" pans. Can't imagine baking in a 4" pan, myself.

HTH

I guess I hadn't considered the trade off of just baking a 2", refilling the pan and doing it again... since a 4" really would take sooo long.