A childhood belief about nasty food

When i was young, we would visit my grandparents in west texas. My gr-pa would buy tamales off the back of a truck from a mexican woman. He would tell me they were "cat tamales" and if i looked in the back of her truck i would see the cat heads rolling around. He would make a "meow" sound when someone bit into one of the tamales. (of course later, my grandfather and grandmother told me that was a joke and in fact the lady made some of the best tamales in town) lol