If I am on tour and know I will have a hard day with few or no service en route I will pack a single-serv package of Hammer Perpetuem. Calories and hydration at the same time.
I did this fully loaded on coffee and 6 fig bars (the 3" kind) for breakfast, two Gus, an apple and a bottle of Perpetuem:
Routes · Ride with GPS
I was hungry at the end but never felt I needed more fuel while on the road. At the end of the ride, I treated myself to the best fried chicken and JoJos I have ever had.