1. Bring a large pot of salted water to a boil. Add the tortellini and cook according to the package instructions (typically around 8 to 10 minutes) until they are al dente. Drain the pasta and set it aside.
2. Pat the diced chicken breasts dry with paper towels. Season the chicken with Cajun seasoning, salt, and black pepper. Toss to ensure even distribution.
3. In a large skillet, heat the olive oil over medium-high heat. Add the seasoned chicken pieces and cook for 5 to 7 minutes, stirring occasionally, until golden brown and cooked through. Remove from skillet and set aside.
5. Stir in the grated Parmesan cheese and an additional 1/2 teaspoon Cajun seasoning. Taste and adjust salt if needed.
6. Return the cooked chicken to the skillet with the sauce, then add the cooked tortellini. Toss everything together until the pasta is fully coated in the sauce. Serve hot garnished with fresh chopped parsley.