½ cup freshly grated parmesan cheese, plus more for topping
freshly cracked black pepper, as needed
Bring a large pot of heavily salted water to a boil.
Meanwhile, heat a 3-quart stainless steel sauté pan over medium-high heat. Once hot, add enough olive oil to coat the bottom. Add the sausage. Use a wooden spoon to break it apart into smaller pieces. Season with a pinch of salt. Cook the sausage until browned, about 5 minutes. Use a slotted spoon to transfer the sausage to a plate and set aside.
Reduce the heat to medium. Add the butter. Once melted, add the onion and fennel. Cook for about 8 minutes until caramelized and tender, stirring often. Season with a good pinch of salt.
Drop the pappardelle into the boiling water, stir well, and cook to “al dente” according to the bag’s instructions.
To the onions and fennel, add the garlic. Cook for 30 seconds. Stir in the tomato paste and calabrian chili paste, and cook for another minute or so. Pour in the white wine. Allow the wine to simmer for 2 minutes.
Add the tomato purée, heavy cream, oregano, and browned sausage. Retrieve 1 cup (plus a little extra on the side if needed) of starchy pasta water and add it to the sauce. Stir well to combine. Bring the sauce to a bubble, reduce the heat to medium-low, and simmer for about 5 minutes, stirring occasionally.
Drain the pasta and add it right back to the large pot. Pour in the sauce and toss to combine. Gradually add the parmesan cheese, stirring until it melts and the sauce clings to the pasta. (If the sauce is too loose, raise the heat to medium and continue to stir until it thickens. If it’s too thick, add in a little more pasta water.)
Season with salt to taste. Plate the pasta with freshly cracked black pepper and more parmesan over top.