Joconde sponge

Joconde sponge refers to a thin, tender cake based on almond powder, whole eggs, icing sugar, flour and beaten whites, spread in a thin layer on a tray. Its suppleness allows it to be rolled or cut into strips. It forms the classic base of the opera cake and is often used to line entremets, notably in the form of a striped patterned sponge used as a decorative outer band.