While there are many theories about its origin, the most popular one suggests that it was invented in the early 20th century by chef Clémence Lefeuvre in a small village near the city of Nantes in France, when she forgot to put eggs into the Béarnaise sauce she was making for fish. A specialty of Aix-en-Provence, calissons are diamond-shaped sweets made with almonds and candied melons, covered in icing.
