the.com/casserole

the noun that turns leftovers into a respectable dish nobody can identify but everyone finishes

means A baked dish of mixed ingredients cooked slowly in a deep oven-safe pot, or that pot itself.

from From French casserole, a diminutive of casse (a pan or ladle), which traces back through Provençal cassa to Late Latin cattia, meaning a ladle or pan — itself possibly borrowed from Greek kyathion, a little cup. So the word began life as the vessel and only later came to mean the comforting jumble cooked inside it.

french root: Means saucepan; the dish stole the pot's name
funeral fuel: The official food of American grief and church basements
binder magic: Cream-of-something soup secretly holds half of them together
green bean classic: Invented in 1955 by a Campbell's test kitchen
one-dish empire: Cooking and serving vessel in a single cunning move

for instance

green bean casserole — created by campbell's in 1955, the most popular thanksgiving dish in america with millions served annually

tuna noodle casserole — american comfort food staple combining canned tuna, egg noodles, and cream of mushroom soup, peaked in popularity 1950s-1970s

french onion casserole — traditional french dish of caramelized onions with bread and melted gruyère cheese, foundation of french onion soup