Preheat oven to 400 degrees. Cut the butternut squash in half, long ways and remove the seeds and pulp. Rub some olive oil on it, and put it in the oven on a baking sheet. Let cook for about 30 minutes.
After the squash has been in the oven for about 20 minutes, heat some olive oil and butter in a soup pot over medium heat.
Add the pancetta and let crisp up and brown a bit, 5 minutes. Next, add shallots, celery, and carrots . Add salt, pepper and red pepper flakes to mirepoix and let cook for 10 minutes, until vegetables are softened.
Add the rosemary and white beans to the mixture and let the beans soak up the flavors for about 5 minutes. Add a little more salt and pepper to the mixture,.
Add all the stock to the pot, raise the heat and bring to a simmer. Add the garlic and let simmer for 10 minutes, until garlic is soft. Turn off heat.
Remove the squash from the oven and add to the pot. With an immersion blender, blend the mixture until smooth. (You could strain through a fine mesh sieve if you wanted it to be super smooth, but I don't)
Mix in the half and half/cream and Parmesan cheese and keep on very low heat until ready to serve.