Boil a large pot of salted water and cook the penne pasta according to package instructions until al dente.
While pasta cooks, toss the chicken cubes with 1 tablespoon of Cajun seasoning and salt in a mixing bowl.
Heat olive oil in a large skillet over medium-high heat and sear the chicken until fully cooked and browned, approximately 6 to 8 minutes. Remove chicken from skillet and set aside.
In the same skillet, melt the butter and sauté the minced garlic for 1 minute until fragrant.
Deglaze the skillet by pouring in the chicken broth and heavy cream, scraping the bottom of the pan to release any browned bits.
Whisk in the remaining 1 tablespoon of Cajun seasoning and simmer for 3 to 5 minutes until the sauce begins to thicken.
Reduce the heat to low and stir in the Parmesan and mozzarella cheeses until fully melted and the sauce is smooth.
Drain the pasta and add it to the skillet along with the cooked chicken. Toss thoroughly to coat everything in the cheese sauce.
Garnish with fresh parsley and serve immediately.