Hi,
I'm starting a 2,175 mile hike next month up the Appalachian Trail and trying my hardest to plan healthy meals along the way. I plan to create supply packages that I'll have family mail to me along the way, so that I'm able to eat healthier versus eating only what I can find in small trail towns.
I'm concerned with malnutrition. I plan to hike 25-30 miles a day (3 month trip) and estimate I'll be burning somewhere between 4000 and 6000 calories a day. Normally I don't concern myself these matters and favor quality over quantity, while listening to my body; however, this will be a little more extreme than my normal day life so I'm trying to be more cautious.
My cooking supplies will be limited -- alcohol stove, .9L cooking pot, and spork

I intend to have grain as a stable (by allowing it to soak overnight/during the day) but trying to figure out how to increase my caloric intake.
Are there any suggestions on what types of foods I should consider? I haven't had much luck researching this topic as most reference books on this topic just recommend eating lots of pop-tarts, potatoes, and peanut butter.
Thanks for reading all this and for any suggestions!
Damon