Add the chicken breasts to the crockpot.
Season the chicken with fajita seasoning, garlic powder, onion powder, and smoked paprika.
Add the sliced red bell pepper, orange bell pepper, yellow bell pepper, purple onion, undrained Rotel, and cubed cream cheese to the crockpot.
Cover and cook on High for 3 hours, or until the chicken is fully cooked and tender.
Shred the chicken directly in the crockpot and stir everything together until the cream cheese is fully melted and combined with the sauce.
Add the cooked pasta and the entire bag of shredded Mexican blend cheese. Stir until the cheese is melted and everything is creamy and evenly combined.
Top with fresh chopped parsley for a pop of color and serve hot.