hi. i have been asked to do a open bible cake for 100 people. what sz pan can i use and can i double the pans for 2 layer? thanks

You could use 2 12x18 pans side by side. In the middle where they meet just trim off a little more. On the sides just slant it down. If the centers of the cakes have a little hump, just leave it. It makes it look more realistic as a book. If you want to stack them, then you would have to carve some from the center and some from the sides to get the book effect. I have done the side by side. Have not done the stacked.

ive done it the way barbarajean has and there is a pic in my profile of it so you have a visual if that helps