Did Field ovens for bread baking exist?

[Paullus Scipio]

So perhaps some of the "frying" pans found were actually for use
baking bread in the earthern field ovens contructed in the temporary camps?

........any flat pan can be used for making bread over a small open fire - no oven needed...in India, a flat griddle(karhai) is used to make chappatis, pooris and many other kinds of flat bread, and is also used as a 'frypan', griddle etc for general cooking.

Here in Australia, a 'camp oven' ....the bushman's essential cooking device, consisting of a cast-iron casserole dish with a flat lid, so coals can be heaped on top,..... is used to make everything from bread, through full breakfast, stews, dinners and anything you care to name!!
There are whole cookery books....dozens of them......filled with recipes to be cooked in 'camp ovens'......a relatively small one suffices to cook sufficient for half-a-dozen drovers (cowboys).

I don't doubt a 'camp oven' would keep a contubernium well fed indeed, and if married to a flat griddle for quick,'flash' cooking in a hurry ( the slower camp oven for more leisurely occasions), all needs could be met......