Rub the chicken breasts with Cajun seasoning, garlic powder, paprika, salt, and pepper. Marinate for 15-20 minutes.

Place marinated chicken in the slow cooker, add bell peppers and onion, pour chicken broth over them. Set cooker to low for 6-7 hours or high for 3-4 hours.

After cooking, check that chicken is tender and shred it in the slow cooker with two forks, mixing with the veggies and broth.

Stir in cream cheese and Parmesan cheese, mixing until melted and creamy, about 10-15 minutes on low heat.

Cook the pasta separately until al dente, then drain and set aside.

Combine the cooked pasta with the creamy chicken mixture in the slow cooker and serve garnished with parsley and red pepper flakes.