Place the chicken breasts into the crockpot.
Add the onion, garlic, chicken broth, diced tomatoes, tomato sauce, Italian seasoning, basil, oregano, salt, and black pepper.
Cover and cook on Low for 6 to 7 hours or High for 3 to 4 hours, until the chicken is fully cooked and tender.
Remove the chicken and shred it using two forks.
Return the shredded chicken to the crockpot.
Stir in the softened cream cheese until completely melted.
Add the heavy cream and Parmesan cheese, stirring until smooth and creamy.
Fold in the cooked pasta.
Cover and cook for another 10 to 15 minutes until heated through.
Garnish with fresh parsley or basil and extra Parmesan before serving.