One variant of leek soup is vichyssoise, which is generally served cold. It is often claimed that he created vichyssoise soup, though this is unproven and disputed. President Kennedy was especially fond of "La Caravelle"s vichyssoise and chicken in champagne sauce. Vichyssoise was served the rest of the summer and the following summers. Louis Diat ran the kitchens and invented Vichyssoise there. Charles M. Schwab was the first to sample vichyssoise and requested another serving.