Cook the penne pasta according to package instructions until al dente. Drain and set aside.
In a large skillet, heat the olive oil over medium heat. Add the sliced smoked sausage and cook until browned, about 5-7 minutes.
Add the diced onion to the skillet and sauté until softened, about 3-4 minutes. Stir in the minced garlic and cook for an additional 1 minute until fragrant.
Pour in the heavy cream and chicken broth, then add the Italian seasoning. Stir to combine and bring to a gentle simmer.
Reduce the heat to low and stir in the grated Parmesan cheese until melted and the sauce is creamy. Season with salt and pepper to taste.
Add the cooked penne pasta to the skillet and toss to coat the pasta evenly with the sauce. Cook for an additional 2-3 minutes to heat through.
Serve hot, garnished with fresh parsley.