Eton Mess
Image: Jennifer Lyons
Served at prize-giving day at Eton College on the 4th of June. There is evidence that other fruits, including banana, have been used and that spirits such as whisky or Kirsch are sometimes added.
Known at least since 1896, when A. H. Beavan's Marlborough House & its Occupants refers to it as being served to the Royal party (OED)
Eton College
Cantabrigia Illustrata, 1690.