Load the crockpot: Add the chicken, broth, garlic, Italian seasoning, salt, and pepper to the crockpot.
Cook: Cover and cook on low for 6 hours or high for 3 hours, until the chicken reaches 165°F and shreds easily.
Shred: Shred or cube the chicken and stir it back into the broth.
Build the sauce: Add the cream cheese, heavy cream, parmesan, and butter. Stir until fully melted and smooth, about 5-10 minutes on low or warm.
Serve: Toss with cooked pasta or spoon over it, and top with extra parmesan and parsley.
Notes
Add the cream cheese, cream, and parmesan only in the last few minutes, never at the start, or the sauce will break over the long cook. Cook pasta separately.