Place the chicken breasts in a single layer at the base of your slow cooker.
In a mixing bowl, combine the chicken broth, cream of chicken soup, garlic powder, onion powder, Italian seasoning, salt, and pepper. Stir until smooth and well-blended.
Incorporate the cubed cream cheese into the sauce mixture, then pour the entire blend evenly over the chicken in the slow cooker.
Cover with the lid and cook on the low setting for 4 to 6 hours, or on high for 2 to 3 hours, until the chicken is cooked through and tender (internal temperature should reach 165°F / 74°C).
Roughly 30 minutes before the cooking time concludes, use two forks to shred the chicken directly in the slow cooker. Add the shredded mozzarella and grated Parmesan cheese, stirring until evenly distributed. Cover again and allow the cheese to melt into the sauce.
Before serving, sprinkle with fresh chopped parsley. Serve hot alongside pasta, steamed rice, mashed potatoes, or crusty bread.