- Heat oil in a large pot over a medium heat.
- Add onion, celery, basil and garlic to pan. Cook for 10 minutes, stirring often.
- Stir in tomatoes and vegetable stock. Bring to the boil then simmer for 15 minutes.
- Drain and rinse the beans and add to the soup with the spinach. Stir and cook for a further 3 minutes, or until the spinach has wilted.
- Serve immediately with warm crusty bread.
Try adding chopped chorizo to this soup for a spicy kick.