Bring a large pot of salted water to a boil. Cook penne pasta until al dente, according to package instructions. Drain and set aside.

Heat 1 tbsp olive oil in a large skillet over medium-high heat. Season chicken with Cajun seasoning, salt, and black pepper. Cook until golden brown and cooked through, about 5-6 minutes. Remove and set aside. Add sausage slices to the pan, cook for 2-3 minutes, then remove. Add shrimp and cook for 2 minutes per side until pink. Remove from the skillet.

In the same skillet, add 1 tbsp olive oil and sauté onions, bell peppers, and garlic until fragrant. Stir in diced tomatoes, smoked paprika, and red pepper flakes. Pour in heavy cream and chicken broth, then bring to a simmer. Let cook for 5 minutes before stirring in Parmesan cheese.

Return the cooked chicken, sausage, and shrimp to the skillet. Add the drained pasta and toss everything together until well coated in the sauce. Sprinkle with fresh parsley and serve hot!