When traveling, I make a sandwich right after my breakfast / coffee in preparation for the day. I will eat half each time and it will get me through the day until I set camp and make some dinner.

I like an iced coffee in the afternoon, which is easy to do as the coffee in my thermos is usually almost cold.... so a couple of chunks of ice in a cup from a gas stop and a creamer will make a free delicious snack to go with the other half of that sandwich.