The date of production of Charpentier’s The Cup of Chocolate of 1768 has always raised questions on account of it being impossible for the five protagonists to have been present simultaneously in that year. Several other paradoxical elements lead us to question this dating. A close examination of the virtual images depicted in the mirrors shows deliberate perspective ‘errors’. The geometric reconstruction of the ‘true’ virtual images and the discovery of the inscription ‘Charpentier 76’ on the painting The Duke de Penthièvre and His Daughter Louise-Adélaïde, which is contemporaneous with the latter work allows us to adjust the chronology and to link to these two paintings a third one, Gautier-Dagoty’s The Duke and Duchess of Chartres. In this light, the interpretation of The Cup of Chocolate needs to be revisited. Far from being a banal ‘conversation piece’, it constitutes not only a veritable nostalgic memento mori evoking the memory of the Countess of Toulouse and the Prince de Lamballe; it is also an explicit tribute to the Princess de Lamballe who was honoured by the friendship of Queen Marie-Antoinette.