Mozzarella Cheese (if we're thinking of the same cheese sticks) Is surprisingly low in fat and high in protein, this makes it a viable option for lighter diets.
Cottage cheese (I can't stomach the **** though).
Ham steaks - no really bulk specific but hell, I can't think of a better way to way up...
...Besides maybe bacon!
Real mother ****ing macaroni and cheese (not that kraft bull****)
Fry everything you got in oil, don't use pam or the non-stick sprays
Basically rethink all the foods you've been avidly avoiding over the years. If it's not processed chances are you can easily work it into your diet.