Cut spring onions, garlic and broccoli and sauté it on mixture of olive oil and butter for just 2-3 minutes. Add water (1 liter+) salt, pepper and celery and cook 30 minutes or until broccoli become soft. When it become soft use blender or stick blender to make a creamy soup. Add semolina and cook for 10 more minutes. In the meantime cut pancetta into very thin pieces and fry them until crunchy. Put the pancetta onto a paper towel to soak fat. When the soup is ready to serve add heavy cream. Serve with croutons and pancetta sprinkled over croutons.