Fried onion burger

A fried onion burger, also called an Oklahoma onion burger, is a regional American burger style and specialty of Oklahoma cuisine. The dish was created in El Reno, Oklahoma, in the 1920s by a restaurateur searching for a way to stretch ground beef with a less expensive ingredient in order to cheaply feed striking railroad workers during the Great Railroad Strike of 1922. Its primary ingredients are thinly sliced onions and ground beef.

Description: Wikipedia — Fried onion burger, CC BY-SA 4.0