Step 1: Place the boneless, skinless chicken breasts at the bottom of the crockpot.
Step 2: In a separate bowl, mix together the cream of chicken soup, cream of mushroom soup, chicken broth, softened cream cheese, garlic powder, Italian seasoning, salt, and black pepper until smooth.
Step 3: Pour the creamy mixture over the chicken in the crockpot, ensuring the chicken is well coated.
Step 4: Cover and cook on low for 6-7 hours or on high for 3-4 hours, until the chicken is cooked through and easily shreds with a fork.
Step 5: Once cooked, remove the chicken from the crockpot and shred it using two forks. Return the shredded chicken to the crockpot and stir to combine with the sauce.
Step 6: Break the uncooked spaghetti in half and add it to the crockpot. Stir to ensure the spaghetti is submerged in the sauce. Cover and cook on high for an additional 30-40 minutes, or until the spaghetti is tender.
Step 7: Stir in the grated Parmesan cheese and shredded mozzarella cheese until melted and well combined.
Step 8: Serve hot, garnished with chopped parsley if desired. Enjoy your creamy chicken spaghetti!