This recipe is from the Everyday Food cookbook. Shallots are sauteed in butter, and flour is added to the mixture to create a thicker soup base. Fresh asparagus, water, salt and thyme are added to the shallots and the whole mixture is brought to a simmer. Once the asparagus is tender, the soup is transferred to a blender and pureed until smooth. Lemon juice and heavy cream are stirred in at the end. The nice thing about this recipe is that it made enough for me to freeze a few servings. To freeze this soup, omit the lemon juice and cream. These ingredients should be added in when you reheat the frozen soup.