Drizzle olive oil over the chicken breasts, covering them well. Generously sprinkle Cajun seasoning, garlic powder, onion powder, smoked paprika, salt, and black pepper over the chicken, rubbing in the spices.

In a skillet over medium heat, add olive oil and warm. Place the seasoned chicken breasts in the skillet, browning for about 2-3 minutes on each side until golden.

Lift the browned chicken from the skillet and place it in the slow cooker, keeping any drippings to enhance flavor.

Layer sliced bell peppers, diced onion, and minced garlic over the chicken in the slow cooker.

Pour diced tomatoes and chicken broth over the ingredients in the slow cooker, ensuring everything is evenly coated.

Cover the slow cooker and cook on low for 4-5 hours or high for 2-3 hours until chicken is tender.

Once cooked, shred the chicken with two forks in the sauce.

Stir in the heavy cream and grated Parmesan cheese until fully melted and integrated.

Boil the penne pasta separately according to package instructions, then drain and set aside.

Add the cooked pasta to the slow cooker with the creamy chicken mixture and toss together.

Cover and heat for another 15-20 minutes on low.

Serve generous portions garnished with freshly chopped parsley.