Preparation Steps:

• Start by cutting the chicken breasts into 1-inch pieces. Slice the bell peppers into strips, and thinly slice the red onion. Mince the garlic cloves, and set everything aside.
• In a large pot or Dutch oven, heat 1 tablespoon of olive oil over medium heat. Add the chicken pieces and sprinkle them with 1.5 tablespoons of Cajun seasoning. Cook for about 5-7 minutes, stirring occasionally until the chicken is browned and cooked through. Remove the chicken from the pot and set it aside.
• In the same pot, add the remaining 0.5 tablespoon of olive oil. Toss in the sliced bell peppers and red onion. Sauté for about 3-4 minutes until the vegetables start to soften. Then add the minced garlic and cook for an additional 1 minute until fragrant.
• Pour in the two cans of low-sodium chicken broth and the can of fire-roasted diced tomatoes. Stir to combine, scraping up any browned bits from the bottom of the pot.
• Add the penne pasta to the pot, stirring to ensure it is submerged in the liquid. Bring everything to a boil, then reduce the heat to a simmer. Cover the pot and cook for about 10-12 minutes, stirring occasionally, until the pasta is al dente.
• Once the pasta is cooked, stir in 0.5 cup of heavy cream. In a small bowl, mix the cornstarch with 1 tablespoon of water to create a slurry. Add this to the pot and stir well to thicken the sauce.
• Remove the pot from heat and stir in the remaining 0.25 cup of heavy cream and 0.75 cup of finely shredded Parmesan cheese. Mix until the cheese is melted and the sauce is creamy. Season with salt and freshly ground black pepper to taste.
• Spoon the creamy pasta into bowls, then sprinkle with 3 tablespoons of minced fresh parsley for a touch of freshness. Enjoy your One Pot Cajun Chicken Pasta while it's hot!