Apparently the simplicity of my meal drew lots of questions from the group. A few of the Sierra Club members we were camping with seemed impressed that I had just opened a full box of mac-n-cheese and dumped in a can of chicken for a scrumptious, and quite filling dinner.
However, I could have eaten a lot less food that night. To make a better portioned meal, I would cut the mac-n-cheese noodles in half when packing it and still use one and a half cups of water to heat it in the cozy. Then I would drain the noodles, and add the flavoring mix afterwards. Cutting the flavor packet in half shouldn't be too difficult. I would also use a quart-sized freezer bag to cook in, because they seem to hold up better to the heat of boiling water. Adding a quarter cup of dried vegetables to the mac-n-cheese mix would make it a much more nutritious meal, and this could be done before the water is added. I'll try this out at home. Once I get the details worked out, I'll publish the recipe.