Serves 4 persons - preparation time: 20 minutes
Wash and clean the radishes, reserving the radish greens. Slice the avocado in half lengthwise, remove the stone, and scoop out the avocado flesh.
Purée the avocado, radish greens, spinach, lemon juice, and water until smooth. Season the soup with salt, pepper, and sugar and place it into the refrigerator to chill until serving time.
Coarsely chop the radishes. Ladle the chilled soup into soup bowls and add the radish pieces. Crumble the fresh goat cheese and sprinkle it over the soup.