Make a savory trifle... slice pieces as suggested in egg and panko, then fry like polenta slices; layer with sliced tomatoes, caramelized onions, and parmesan cheese, then broil so the top gets browned.
My mom used to make this when I was little. Leftover mac n cheese, splash of milk, small can of bushes baked beans and cut up hotdogs. It sounds kinda gross but believe me it is good.She called it little angel casarole.
I actuallly just frooze a few lunch sized packages to bring to work. In the morning before heading out the door I throw some frozen chopped greens into a container and then the froozen mac and cheese and pretty well defrosted by lunch, it was really good!
Mix in some chopped chipotles in adobo sauce. It really kicks up the mac and cheese. Topped with garlic crumbs it's another experience entirely. I have to confess that I'm also secretly addicted to deep-fried mac-n-cheese.