Bring a large pot of salted water to a boil and cook the penne according to package directions until al dente. Drain and set aside.
Heat the olive oil in a large skillet over medium heat. Add the Italian sausage and cook, breaking it up with a spoon, until browned and cooked through.
Add the diced onion to the skillet and cook for 3 minutes until softened. Stir in the minced garlic and cook for 1 minute more.
Mix in the chopped sun-dried tomatoes and Italian seasoning. Cook for another minute to blend the flavors.
Add the chopped kale and stir until it begins to wilt, about 2 minutes.
Pour in the heavy cream and bring to a gentle simmer. Season with salt and black pepper.
Add the drained pasta to the skillet and toss to coat evenly in the sauce. Stir in the grated Parmesan until melted and combined.
Serve immediately while hot.