Heat the oil up in a heavy based saucepan.
Add in the onion, smoked bacon, celery and carrots and leave to cook for 10 minutes over a moderate heat. Add in the rosemary, tomato puree, beans, tomatoes and stock. Bring the mixture to the boil.
Reduce the heat and leave to simmer for 10 minutes until the beans are heated through. Remove and discard the rosemary stalks.
Using a ladle, add one third of the mixture into a blender and blend into a puree. Then return the pureed soup to the saucepan.
Bring the mixture back up to the boil and add in the pasta. Allow to cook for 10 minutes uncovered (or until the pasta is fully cooked through). Remove the pan from the heat.
Check for seasoning adding salt and freshly ground black pepper. Ladle into soup bowls, sprinkle over the grated parmesan and serve immediately.