A sort of standard lunch staple for my wife and I are tortillas with PB and instead of jelly we just stick some sort of dried fruit in there and roll it up. It works fine for a week or so trip, and different dried fruits can add a bit of variety. And tortillas are a good choice if you're carrying a bear can, they pack in there pretty space-efficiently.

However, after a few days of this every day I get sick of it. What I plan to do in future is carry some Fantastic Foods Refried Bean powder and mix up the bean paste right in the tortilla (cold). Per recommendation from Yo Yo of PCT fame, this works well, at least for me. Also per his recommendation a few crushed corn chips adds something to the mix, and of course, some olive oil. Soon you go from a moderate calorie lunch item to a relatively high calorie meal !

Anyway, if you are carrying tortillas on longer trips, I think it's good to have multiple things you can fill 'em with unless you're the type of person that really can happily eat the same bloody thing day after day ...