This is sort of a cooking question, and it is sort of a MYOG question.
I have a standard recipe for Boston Brown Bread, and in traditional style, this bread is baked inside ordinary wide steel cans, like for vegetables or fruit. It works good and lasts a long time.
Now, for backpacking purposes, I want to do the same recipe, but I want to bake it into narrow round loaves about the size of a Hostess Twinkie. You can understand the desire for a compact food. However, I can't find any steel cans that small in diameter. The correct size would be about like a Red Bull can, except that it must be steel. An aluminum can might not survive the oven baking. Also, I will probably need to adjust the baking time somewhat.