Bring a large pot of salted water to a rolling boil. Add the penne pasta and cook according to package instructions, typically 10-12 minutes, until al dente. Drain and set aside.

In a large skillet, heat 2 tablespoons of olive oil over medium heat. Season the chicken breast with Cajun seasoning and cook for about 4-5 minutes until golden brown. Remove and keep warm.

In the same skillet, add a drizzle of olive oil and add the shrimp. Cook for 2-3 minutes until they turn pink. Remove and set aside with the chicken.

Return the skillet to medium heat and add more olive oil if needed. Add the andouille sausage and cook for 2 minutes. Then add bell peppers, red onion, and garlic, stirring until tender, about 4 minutes.

Reduce heat to medium-low and pour in the heavy cream, stirring constantly for 2-3 minutes. Gradually add Parmesan cheese until melted. Season with salt and pepper.

Add cooked chicken, shrimp, and drained penne pasta to the skillet. Toss to coat evenly and heat through for 1-2 minutes.

Sprinkle chopped parsley over the pasta and serve immediately.