Bring a large pot of heavily salted water to a rolling boil over high heat.

In a large sauté pan, heat a drizzle of olive oil over medium-high heat. Add sausage, breaking it into smaller pieces. Cook for about 6-8 minutes until browned. Transfer sausage to a plate.

Lower heat to medium, add butter to the same pan. Once melted, incorporate diced onion and fennel, cooking for about 8 minutes until caramelized.

Stir in finely chopped garlic and cook for an additional minute. Add tomato paste and Calabrian chili peppers, then pour in white wine to deglaze, simmering for about 2 minutes.

Incorporate tomato purée, heavy cream, and chopped oregano. Stir in the sausage. Let sauce simmer gently for about 5 minutes.

Add egg pappardelle pasta to boiling water. Cook according to package instructions, typically 3-5 minutes until al dente. Reserve a cup of pasta water before draining.

Drain pappardelle and add to the pan with the sauce. Toss over low heat to coat the pasta.

Sprinkle in the freshly grated parmesan cheese, stirring until it melts. Adjust consistency with reserved pasta water as needed.