It is attributed to Louis Diat, a chef from Montmarault, son of a shoe merchant, who developed his passion for cooking and became an apprentice pastry chef in Moulins at the age of 14. He returned to the Ritz in Paris as head of the kitchen before climbing the ranks in London.
Later, he moved to New York, where he became the head chef at the New York establishment when it opened its doors in 1910. Seven years later, on a hot summer day, he invented the famous leek and potato soup, recalling a recipe from his grandmother.
As children, he and his older brother had the idea of adding milk to the soup in summer to make it refreshing. At that time, Vichy was already known as a spa city, so he called his dish “crème vichyssoise glacée,” in reference to its lightness. It is a cold soup of leeks and potatoes, strained with double cream and sprinkled with chives.
From the very first day, the soup was an immediate success. Louis Diat liked to say that the first client to try it recommended it immediately. Initially, it was only served in summer, but due to demand, in 1923, it was added to the menu every year.
In winter, it was served hot. The soup enjoyed great popularity, and Sara Delano Roosevelt, the President’s mother, once called in the middle of the night to have canned food sent to her. As a gift, she gave him the recipe, which he later published in the book Cooking à la Ritz. In the 1930s, the name of the soup was changed to Crema Vichyssoise Glacée. It then spread throughout the country under the name vichyssoise.
