My worst meal was on a Boy Scout hike when I was 15. We were making flap-jacks in a cast-iron frying pan (man I'm glad those days are long gone!) and using meadow muffins (aka cow patties, buffalo chips) for firewood. The batter was prepared and sitting next to the fire while the pan got hot. Soon the cakes were cooking, but because we had to do them one at a time the fire needed to be restoked about 3/4 of the way through the batch. I ate one of the last pancakes - about half of it - when I discovered a lump that wouldn't bite through. I spit it out - it was a chunk of cow dung! The kid stoking the fire wasn't particularly careful about what container he carried the chips over.

It's amazing how a little bit of poop can spoil an otherwise good meal.