A madeleine is a traditional sweet from France. Madeleines are identified by their distinctive shell-like shape, which they acquire from being baked in special pans with shell-shaped depressions. Madeleines are cake-like and fairly small. Their flavour is similar to, but somewhat lighter than, pound cake, with a pronounced butter-and-lemon flavour.
Madeleines are perhaps most famous outside of France by their association with Marcel Proust's novel Remembrance of Things Past, in which the narrator's memories of childhood are awakened by the aroma and taste of a madeleine dipped in tea.