I bring a regular lunch in a "cooler bag" and toss it in my pannier. I have a longer ride so I eat a decent amount during the day. Its usually a mix of protein, carbs, water and yes sweets. Today I have a couple small PBJ's, a ham sandwich, fig newtons, a granola bar and banana. Yesterday included a nice boiled chicken breast. Some days are healthier than others, LOL. I may not eat it all, but at least I have it so I don't bonk after a long day at work.

The only thing I avoid is something too salty or too large in size.