Cook pasta per package instructions. Drain.
Place the chicken into a bowl. Sprinkle with 1 1/2 teaspoons of the Cajun spice mix and toss to coat.
Heat a large skillet or pot over high heat. Add 1 tablespoon of the butter and 1 tablespoon of the oil. Once hot, add the chicken. Without stirring, let brown slightly on one side. Toss and brown the other side. Remove to a plate or large bowl.
Add the remaining butter and oil and heat.
Add peppers and onions and cook 2-3 minutes. Add the garlic and remaining Cajun spice mixture. Stir and cook another minute.
Add tomatoes and cook for 1 more minute. Remove all vegetables to a plate or bowl (you can use the same one you used for the chicken).
Add the chicken broth to the pan, and cook over high heat, stirring for 5 minutes to reduce.
Reduce heat to medium low and slowly stir in the cream.
Add in the cayenne pepper, black pepper and salt, to taste. Don't be shy with the cayenne, you want the sauce to have some kick!
Let cook, simmering, for 5 minutes or until the sauce starts to thicken.
Add the chicken and vegetables back to the pan. Stir.
Finally, stir in the pasta, mix well, and heat through.
Serve garnished with chopped parsley.