Prep the crockpot: Lightly spray the slow cooker insert with cooking spray to prevent sticking and make cleanup easier.
Add the chicken: Place chicken breasts in a single layer on the bottom. If using large thick breasts, cut them in half for even cooking.
Build the sauce base: In a bowl, whisk together cream of chicken soup, chicken broth, Italian dressing mix (or homemade blend), garlic, pepper, and salt.
Pour and top: Pour the sauce over the chicken.
Scatter the cream cheese cubes across the top so they melt evenly.
Cook low and slow: Cover and cook on Low for 4–5 hours or on High for 2.5–3.5 hours, until chicken shreds easily.
Shred and enrich: Remove chicken to a plate and shred with two forks. Whisk the sauce in the crock to fully blend the melted cream cheese. Stir in Parmesan.
Adjust consistency: Return shredded chicken to the sauce.
If it’s too thick, stir in milk or half-and-half, 2 tablespoons at a time, until it’s creamy and pourable.
Taste and finish: Adjust salt and pepper. Garnish with chopped parsley or basil.
Serve: Spoon over hot pasta, rice, or mashed potatoes. Add extra Parmesan if you like.