In a bowl, mix together the chicken breasts with olive oil, Cajun seasoning, garlic powder, onion powder, smoked paprika, salt, and black pepper until evenly coated.

Heat a skillet over medium heat and add the seasoned chicken breasts. Sear for 2–3 minutes on each side, or until golden brown. Transfer the chicken to the slow cooker.

In the slow cooker, layer the sliced bell pepper, thinly sliced onion, and minced garlic on top of the browned chicken.

Pour the can of diced tomatoes, including their juices, and the chicken broth over the vegetables and chicken in the slow cooker.

Cover the slow cooker with its lid and set it to cook on low for 4–5 hours or on high for 2–3 hours.

Once the cooking time is up, take the chicken out and shred it using two forks. Return the shredded chicken back to the slow cooker.

Stir in the heavy cream and grated Parmesan cheese into the slow cooker until fully combined.

While the sauce simmers, cook the penne pasta according to the package instructions until al dente. Drain the pasta and set aside.

Add the cooked pasta to the slow cooker, gently stirring to combine it with the creamy sauce.

Ladle your Crock Pot Creamy Cajun Chicken Pasta into bowls and garnish with freshly chopped parsley before serving.