Fill a large pot halfway full with water. Bring to a boil and generously season with salt. Add pasta, and cook according to package directions until al dente. Drain; set aside.

While pasta cooks, heat oil in a large skillet over medium heat. Season chicken with salt and pepper to taste; add to hot skillet. Cook until chicken is no longer pink inside and begins to brown, 7 to 10 minutes. Keep warm; set aside.

While pasta and chicken cook, make sauce. Add Alfredo sauce mix, heavy cream, milk, and water to a medium pot over medium-high heat. Whisk ingredients to combine, and bring to a boil, stirring frequently to prevent scalding or lumps. Once sauce boils, reduce heat to low. Add pesto and sun-dried tomatoes; stir until well combined, keep warm.

Add pasta to bowl, top with chicken, and then generous helping of sauce. Top with grated Parmesan cheese.