Cook the pasta as per the box instructions. In a large, deep skillet (non-stick is best) heat 1 Tablespoon of olive oil over medium heat. Add the sausage and use the back of a wooden spoon to break it apart into pieces as it browns. Once it's browned and cooked through transfer it to a paper towel-lined plate. Discard remaining fat from the pan.
Return the pan to the stove and add remaining Tablespoon of olive oil. Add shallots and garlic. Saute until tender, about 4-5 minutes.
Pour in the wine and using the back of a wooden spoon scrape up any browned bits from the bottom of the pan. Add the bay leaf and sage. Cook until the wine has reduced by half, about 3-4 minutes.
Add the stock and pumpkin and stir constantly until the sauce starts to bubble. Add in the cream, pumpkin pie spice, and salt & pepper to taste. Stir until the cream is incorporated into the sauce. Add the sausage back in and simmer the sauce for about 5 minutes to thicken.
Finally, remove the bay leaf and stir together the sauce and drained pasta. Serve the pasta with shaved Parmesan cheese and sage leaves (optional).