Denver omelet is an American dish made with eggs, ham or bacon, onions, and green peppers. In order to prepare it, the mixture is poured into a frying pan, cooked, and folded to form an omelet. Although a plaque on California Street in Denver says that this dish was invented to mask the stale flavor of old eggs, it is more probable that the dish started not as an omelet, but as the Denver sandwich, which is actually a Denver omelet tucked between two pieces of toast.