Within the Cité de l'Océan, Le Sin’s eye-catching wave-shaped architecture commands drop-dead views of the sea and Château d'Ilbarritz. The ingenious chef-craftsman cherry-picks first-rate produce to craft a lineup that adds a new spin to Gallic classics: shepherd’s pie of oxtail with a bordelaise sauce or a fluffy soufflé whose flavour keeps pace with the seasons.