Preparation / Directions:
Cook beets, onion and marjoram in butter in a 4-quart pot over medium heat until onion begins to soften slightly, about 10 minutes. Add broth; partially cover pot and simmer slowly for about 30 minutes, until beets are completely soft.
Check them by trying to crush one against the side of the pod with a wooden spoon. Simmer longer if necessary.
Puree soup in a blender or food processor. If you want soup to have a smoother texture, strain it through a medium mesh strainer. Add cream and vinegar and bring soup back to a simmer. Season with salt and pepper.
To serve, ladle into bowls and garnish with whipped cream, croutons and hers, or serve garnishes separately and let diners help themselves.