Answer:
I am what remains when nothing is left.What am I?
What is given but kept by the giver?
My first is equality; my second is inferiority; my whole is superiority.
People are hired to get rid of me. I'm often hiding under your bed. In time I'll always return you see. Bite me and you're surely dead.
Different lights do make me strange, thus into different sizes I will change
This food is a tortilla filled with cheese and sometimes chicken before being heated or cooked.