1. Season the short rib cubes with salt and pepper.
2. Heat the olive oil in a large pot (6 qt Dutch oven) over medium-high heat. Add the short ribs, sausages, and meatballs. Sear until browned on all sides. Once browned, remove the meat and set it aside on a plate lined with paper towel.
3. In the same pot, add the sliced onion, garlic, bay leaf, and about 15 whole parsley leaves. Cook until the onions are soft, about 5 minutes.
4. Stir in the tomato paste and cook for 3 minutes, stirring occasionally.
5. Pour in the red wine and bring to a boil, scraping up any browned bits from the bottom of the pot.
6. Add the marinara sauce and beef stock to the pot. Return the browned meat to the pot and stir.
7. Reduce heat to medium-low, cover the pot, and let it simmer for 45-50 minutes.
8. While the sauce simmers, cook the fusilli in a pot of salted water according to the package directions. Reserve 1 cup of the pasta cooking water, then drain the pasta.
9. After 45-50 minutes, check the short ribs to make sure they are tender. Cut the sausage into 1” pieces with kitchen shears and remove all the meat from the pot. Arrange the meat on a platter and drizzle with some of the sauce. Garnish with chopped parsley.
10. Add the cooked fusilli to the sauce in the pot. If the sauce is too thick, add some reserved pasta water to loosen it. Stir well and cook for 1 more minute.
11. Drizzle with a little more olive oil, taste for seasoning, and adjust if necessary. Garnish with freshly chopped parsley and serve hot!