The French sandwich cookie made from almond meringue and filled with buttercream or ganache is a macaron.
A Parisian-style macaron consists of two smooth, almond-based meringue shells with a filling such as buttercream, ganache, or jam between them. Properly baked shells have a crisp or delicate exterior, a moist center, and a ruffled edge called the foot, or pied.
The macaron’s history is older than its modern sandwich form. Almond-based versions were made in France for centuries, and two Carmelite nuns in Nancy became famous for selling macarons during the French Revolution. The filled sandwich style emerged in Paris in the early 20th century; Pierre Desfontaines of Ladurée and baker Claude Gerbet are both associated with its development.
Macaron is often confused with macaroon. A macaron uses almond meal and meringue, while an English-language macaroon commonly refers to a denser cookie made with coconut or other nuts. The two names share a linguistic history but describe different familiar pastries.