(including onion skin), skins, left over mashed potatoes, potato peels, carrot tops, celery leaves, spinach leaves, you name it into a pot. It's
cleaned, of course..."
seems exactly like what my grandmother bought at the local produce store, and it was called "soup greens", which seemed to be odds and ends of scrapings and leftovers, very cheap, and usable as a base for her soups...never saw it or heard of it, outside that italian neighborhood of east harlem, but am willing to bet earlier working class areas had the same basic item for sale...
maybe that's why i've never been all that impressed by french cooking, having sampled my grandmother's incredible fare, which achieved major culinary experiences on a meager budget ...
fs