In a Dutch oven or soup kettle over medium-low heat, saute carrots, onion, celery, potatoes, garlic and sugar in oil for 5 minutes. Add broth, nutmeg and pepper; bring to a boil. Reduce heat; cover and simmer for 30-40 minutes or until vegetables are tender.
Remove from the heat and cool to room temperature. Puree in batches in a blender or food processor. Return to the kettle and heat through.