Cornichons are a type of small, tart pickle that are traditionally made from gherkin cucumbers. They are a popular ingredient in French cuisine and are often served as a condiment alongside charcuterie, cheese, and other savory dishes. These pickles are made by soaking small cucumbers in a mixture of vinegar, salt, and spices, which gives them their distinctive tangy and slightly sweet flavor. They are small in size, typically no more than 3-4 cm in length, and are often served whole or sliced.