The green bean casserole was first created in 1955 by the Campbell Soup Company. Dorcas Reilly led the team that created the recipe while working as a staff member in the home economics department. The inspiration for the dish was "to create a quick and easy recipe around two things most Americans always had on hand in the 1950s: green beans and Campbells Cream of Mushroom Soup.
In 2002, Reilly presented the original recipe card to the National Inventors Hall of Fame in Akron, Ohio.
Source: Wikipedia