To reheat roux-based or starch-based thick soups, place a thin layer of water or stock in a heavy-bottomed pot prior to adding the chilled soup. The thin layer of liquid on the bottom of the pot will help to prevent the soup from scorching as it heats. Over medium-low heat, slowly warm the soup up to about 200°F (95°C), stirring often. Once the soup is hot, enrich it, if desired, as described in the lesson. Season the soup to taste and serve in warmed bowls.