In a heavy pot, heat a generous drizzle of olive oil over medium heat. Add diced onion, minced garlic, chopped carrot, and diced celery along with fennel seeds. Cook these aromatics for about 8 minutes, stirring frequently, until softened but not browned.

Increase the heat to high and add the pork and beef sausage into the pot. Use a spatula to break the meat apart as it cooks, ensuring you stir until it loses its pink color—this should take around 5-7 minutes.

Stir in the tomato paste and let it cook for about 1 minute. Next, pour in the red wine and allow it to simmer, reducing by half while scraping up any browned bits from the bottom of the pot.

Now add crushed tomatoes, chicken stock, thyme, bay leaves, salt, black pepper, and optional chili flakes to the pot. Stir well to combine all the ingredients and bring to a gentle simmer.

After the hour is up, carefully remove the pot from the oven. Using a potato masher, gently mash the sausage to break it down further into the sauce.

While the ragu finishes cooking, bring a large pot of salted water to a boil and cook the pappardelle pasta according to the package instructions.

Once the pasta is cooked and drained, add it directly into the pot with the Sausage Ragu. Toss everything together, adding reserved pasta water a little at a time until you reach your desired sauce consistency.

Ladle the Sausage Ragu with Pappardelle Pasta into warmed bowls. Finish with grated Parmesan cheese and freshly chopped parsley.