Potage Parmentier is a traditional potato and leek soup that's usually served hot. It can be served as an appetizer, a side-dish alongside meat courses, or as a stand-alone afternoon snack. The soup consists of potatoes and leeks, or optionally onions, which are cooked and puréed until they develop a smooth, delicate consistency.
Broccoli, asparagus, parsley, or parsnips can also be added to the mixture. In French cuisine, dishes labeled Parmentier will always have potatoes as their main ingredient. This is in reference to Antoine-Augustin Parmentier, the agronomist who made the potatoes popular in France.