Prep the crockpot: Lightly spray the inside with nonstick spray to help prevent sticking and make cleanup easier.
Season the chicken: Place chicken in the crockpot.
Sprinkle ranch seasoning, Italian seasoning, garlic powder, onion powder, red pepper flakes (if using), salt, and black pepper over the top.
Add liquids: Pour in the chicken broth around the sides of the chicken. This keeps the seasoning on top while providing moisture for slow cooking.
Slow cook: Cover and cook on Low for 4–5 hours or High for 2.5–3.5 hours, until the chicken is tender and easily shreds with two forks.
Add the creaminess: About 30 minutes before serving, add the cubed cream cheese, heavy cream, and Parmesan. Stir gently, then cover and let the cream cheese melt into the sauce.
Finish with extras: Stir in sun-dried tomatoes and baby spinach.
Cover for another 5–10 minutes until the spinach wilts and everything is hot and creamy. Taste and adjust salt and pepper.
Shred and serve: Shred the chicken directly in the crockpot with two forks. Stir to coat in the sauce.
Serve over pasta, rice, or mashed potatoes. Garnish with fresh basil or parsley.