Fluffernutter
A fluffernutter is a sandwich made with peanut butter and marshmallow creme usually served on white bread. Variations of the sandwich include the substitution of wheat bread and the addition of various sweet, salty, and savory ingredients. The term fluffernutter can also be used to describe other food items, primarily desserts, that incorporate peanut butter and marshmallow creme. The sandwich was first created in the early 20th century after marshmallow creme, a sweet marshmallow-like spread, was invented in Massachusetts. During World War I, a recipe for a peanut butter and marshmallow creme sandwich, the earliest known example of the sandwich, was published. The term "fluffernutter" was created by an advertising agency in 1960 as a more effective way to market the sandwich.
Source: Wikipedia