Place the boneless, skinless chicken breasts at the bottom of the slow cooker.
Pour in the heavy cream, chicken broth, and minced garlic. Sprinkle in the Italian seasoning, salt, and pepper. Stir everything gently to combine.
Cover and cook on low for 4-6 hours or on high for 2-3 hours, until the chicken is cooked through and fork-tender.
About 30 minutes before serving, add the uncooked fettuccine pasta to the slow cooker. If the sauce feels too thick, add a little more chicken broth or cream.
Once the chicken is cooked, shred it directly in the slow cooker using two forks. Mix it into the sauce.
Stir in the grated Parmesan until fully melted and incorporated, making the sauce extra creamy.
Top with fresh parsley and serve immediately. Enjoy the creamy goodness!