Hi,

I have found for the longer rides I need to make sure I eat on a fairly steady basis - usually about every 20-25 or 70-90 minutes. I usually eat a good breakfast - whole wheat bagel with either eggs or almond butter and a banana. On the rides I tend to do bananas, peanut butter, energy bars. I only use the GUs/Gels for races when I can't really stop to eat. I also have found that if I eat too much as once it impacts my performance so just small amounts paced about 90 minutes apart. If its warm I will use an electrolyte drink under 65 deg usually just water.

Everyone is different so need to figure out what works best for you, some of my friends can eat a big lunch mid-ride. I wouldn't be able to move if I did that. I am also typically pretty hungry afterwards so will eat a good dinner.
The other key is the night before. If am doing a longer endurance ride or race I will make sure to have a good high carb meal the night before.