Broccoli is a good source of fiber and paired with unpeeled potatoes, this soup has lots of fiber.
In a large soup pan, heat oil over medium-high heat. Cook leek, celery, garlic, potatoes, salt and bay leaf until lightly browned.
Add stock and bring to a boil. Reduce heat, cover and simmer 30 minutes.
Add broccoli florets to pot and bring back to a boil. Reduce heat, cover, and simmer another 15 minutes or until all vegetables are tender.
Remove from heat and let cool. Remove bay leaf. Puree soup with a hand blender, until smooth. Serve.