I carry both every day. I have a pannier dedicated to my insulated lunch bag. My bag usually consists of;

1. Morning- p.b. toast w/granola, orange/apple/banana, celery w/p.b., yogurt, granola bar, any combination of above.

2. Lunch- Sandwich/wrap, baked chips, carrots/broccoli w/hummus, fruit, yogurt, almonds, cookie. Soup occasionally. Any combo of above.

3. Afternoon snack- Granola/energy bar/snickers. But i rarely eat one.

I always make my lunch the night before so i can just get up and go. I always have my coffee brewed as i wake up and take it in an insulated mug in my water cage. Some mornings i eat cereal, some days i just eat a granola bar on the train after the first mile.

I eat what i want, and i like what i eat. I make it, it's cheap and it's relatively good for me.

P.S.- don't ever skimp on the bread. Quality bread makes a sandwich. Wheat, not that white garbage.