I eat tons of rice, beans, and pasta to try and bulk up my calories on the cheap. Eating 3500 calories of healthy food costs a fortune, not to mention the sheer bulk of it gets ridiculous. Also we get tons of cereal super cheap, and when I'm riding lots I'll go through that. I'll lose muscle, wattage, and weight if I don't eat enough.

My Lunch/Dinners tend to be heavy in whole foods. All other times I pretty much eat whatever I want. Snacks might be an apple, or 6 oreos on any given day.

PS, often my meals and snacks come from this book:
http://www.amazon.com/The-Feed-Zone-.../dp/1934030767

It's full of high calorie stuff without heavy processing. You'll need a rice cooker for sure.