Hammer Perpetum, or if you have to have solid food their bars are some of the tastiest "energy" bars around. hands down. Havent tried the perpetum solids yet, but those also look like a good choice.

use this link when placing your first order and you get 15% off...and i get free swag...win/win... http://www.hammernutrition.com/affiliates/165508

edit: btw, i practice what i preach..i use Hammer stuff exclusively for riding/training/racing...ive search but there isnt a better system out there.