I know it's nothing new and inventive - but sometimes it's nice to see a simple meal you can make any time with stuff you probably have in your fridge/freezer/pantry.
I took store bought meatballs from BJ's - and baked them per the directions. While they were cooking, I took out the mozz cheese, sliced the rolls, and took out the sauce. You could heat it up I guess - but I'm lazy!
When the meatballs were done, I cut the meatballs in half and laid them on the bottom half of the bun, topped with sauce, then cheese - and put them in the microwave for like :45 sec, just enough to melt the cheese - or while the oven is still hot - just stick it back in there for a few minutes - or without the top on Broil.