I never considered my mom to be a great cook but she did manage to serve us many of these same foods without us gagging: tuna loaf (tuna fish, onions, bread crumbs all smashed together loaf style with the help of an egg), spam w/au gratin potatoes, beets, etc... I can't eat much of that stuff now but back then we did.
However, I could never, never eat a particular snack that she always tried to give us: bananas dipped in OJ and covered with coconut. Don't know why but just the smell of that would make me sick. I'd try to set it aside without too much notice and just sip on the Tab that she would also give us.