In a large pot, heat EVOO over medium-high heat, then add the pancetta and cook, stirring occasionally, until browned and the fat is rendered, 4-5 minutes. Remove from pan and reserve.
Add the sirloin and pork to the pot the pancetta was cooked in and brown well, about 10 minutes. Add the onion, carrots, celery, garlic and cook, stirring, until soft, 4-5 minutes.
Add salt, pepper, allspice, bay leaves and thyme, and cook, stirring, for 30 seconds. Add the reserved pancetta back into the pan and stir in the tomato paste. Cook 3-4 minutes to caramelize. Add in the wine and scrape up all the tasty nibbles that have stuck to the bottom of the pan. Cook until half of the liquid is evaporated, about 2 minutes.
Add the beef stock and bring to a boil. Reduce the heat to medium-low and simmer until the sauce is thickened and flavorful, about 1 1/2-2 hours, stirring occasionally to keep the sauce from sticking to the bottom of the pan.
While the sauce is simmering away, bring a large pot of seasoned water up to a boil. Drop the pappardelle pasta into the boiling water and cook to al dente, according to package instructions. Stir occasionally to prevent the pasta from sticking together.
Add the cream to the sauce and simmer for 2 minutes. Discard the bay leaves and adjust the seasoning, to taste. Remove from the heat and cover to keep warm until ready to serve.
Once the pasta is done, reserve about a cup of pasta water before draining. Drain the pasta and toss it back into the pot it was cooked in along with some of the reserved water, a cup of cheese and a handful or so of the parsley. Add the pasta sauce, reserving enough to top, and toss well to coat.
Serve the pasta in shallow bowls, topped with additional sauce and some additional parsley for garnish. Pass the remaining cheese at the table.