When I did a week-long solo trip on the AT, I loaded up on light and easily made foods- not always the healthiest, but it got me through just fine: mashed potato flakes (choose a good flavor), oatmeal (again, pick something good), soups (that heat up in a few minutes), and occasionally, rice (be sure it is the minute kind if you hike fast/all day). Also, drink mixes (in small bags). This was all I needed (besides your snack list) and suited me very well. I placed all of these individually in small zip-locks and made sure it was airtight.