My trips have all been 4- 6 days so far. Hopefully longer soon...
I've had the best success with a breakfast of granola with extra fresh fruit added (I pack a large bag of it at the start of the trip, but buy the fresh fruit each night before on the road if possible) , a Power Bar every 1 hour or so, and believe it or not Subway for lunch.(depending on availability) I buy a 12" sub, eat half and save half for mid-late afternoon. Good for carbs.
Then once I've found camping for the night, I allow myself a heavier protein meal for recovery (salmon, chicken, whatever's available).
The Power Bars are a lifesaver, I buy a box full to save $$ and carry them all from the beginning of the trip. Don't mind the extra weight, it's worth it.
I also carry a container of powdered Gatorade, another lifesaver.
I avoid milk, it makes me feel heavy and plugged up.
Granola with orange Gatorade instead of milk isn't too bad once you get used to it...
Cheers
Lou