For the next time I want an all-day baking project.

There are many stories about the origins of this cake, known as both Clichy cake and Opéra cake. Many believe that Louis Clichy was its creator because he premiered the gâteau, with his name written across the top, at the 1903 Exposition Culinaire in Paris. It became the signature cake of Clichy's shop on the Boulevard Beaumarchais. However, another pastry shop, Dalloyau, sold a very similar dessert, known as L'Opéra (in honor of the Paris Opera), and some claim that theirs was the original.

Cooks' notes: If you can't find almond flour, you can pulse whole almonds with the confectioners sugar in a food processor until powdery (be careful not to grind to a paste). To take the temperature of a shallow amount of syrup, put bulb in saucepan and turn thermometer facedown, resting other end against rim of saucepan. Check temperature frequently. Opéra cake can be made 2 days ahead. Cover sides with strips of plastic wrap and top of cake loosely with plastic wrap (once glaze is set) and chill cake. Remove plastic wrap from top immediately after removing cake from refrigerator and bring cake to room temperature, 30 minutes to 1 hour.