Bread-Bakers v104.n031.5

For a teenager's birthday supper, I want to serve a giant sandwich made on 
a braided circle bread.

I hope I have described that in a way you can visualize! I have seen them 
at Costco, Sam's, and some deli-bakeries.

I have a round 12" diameter pan I was planning to use although  I could 
find something wider.

Has anyone any suggestions as to quantities of ingredients? Tricks of 
creating such as size of strips? Should I put a form in center? Baking time?

Many thanks, Fredericka