Cook the pasta according to the package directions. Drain the pasta and set aside.

In a large 12-inch skillet over medium-high heat, add the olive oil. Once the oil is hot, add the diced chicken pieces. Cook the chicken for 7-8 minutes or until cooked through and lightly browned on all sides. Transfer the chicken to a plate and set aside while preparing the Cajun sauce.

Turn the heat of the skillet down to medium and add the unsalted butter, diced yellow onion, diced red bell pepper, and minced garlic. Cook for 1-2 minutes, then add the cajun seasoning, salt, and black pepper. Cook for another minute or until the vegetables are cooked through and tender.

Sprinkle the all-purpose flour over the sauteed vegetables and cook just until all the flour has been absorbed into the butter.

Slowly pour the chicken broth into the skillet while whisking constantly until all the flour has been incorporated and no lumps remain.

To the skillet, add the heavy cream and Rotel diced tomatoes. Stir to combine. Allow the sauce to come to a low boil, reduce the heat to low and simmer for 8-10 minutes or until the sauce thickens. Be sure to stir the sauce often to avoid lumps and prevent the sauce from burning.

Once the sauce has thickened, add the cooked chicken back to the skillet along with 2 teaspoons of the chopped fresh parsley. Stir to incorporate.

Lastly, add the cooked and drained penne pasta and the grated parmesan cheese and stir to combine all the ingredients together.

Turn off the heat to the skillet and allow the cajun chicken pasta to sit for 3-4 minutes to allow the pasta to absorb some of the sauce and the sauce to thicken slightly. Garnish with the remaining 1 teaspoon of fresh chopped parsley before serving.