Sorry OP, but it's somewhat funny when people say they eat a ton. I used to say the same thing until I got on a program where I worked my way up to eating 5,000 cals a day for 2 weeks straight.....alot tougher than it sounds actually.
I'd suggest logging your "normal" diet for 1 week. Don't do anything special because you know you're logging it and post it afterwards.
Do you know your base metabolism rate? If not, there are calculators online, just google it. To gain weight, eat approximately 10% above this point.