01 - Preheat oven to 400°F. Lightly grease a baking dish with cooking spray or a small amount of olive oil.
02 - In a medium bowl, combine cream cheese, mozzarella, cheddar, parsley, thyme, garlic powder, onion powder, salt, and pepper. Mix until smooth and well blended.
03 - Place chicken breasts on a cutting board. Using a sharp knife, cut a horizontal pocket into the thickest part of each breast, being careful not to cut completely through the meat.
04 - Divide cheese mixture evenly among the pockets, pressing filling gently into each breast. Secure openings with toothpicks if needed to prevent filling from escaping.
05 - Brush the outside of each chicken breast with olive oil. Season evenly with salt, black pepper, and paprika.
06 - Place stuffed chicken breasts in the prepared baking dish, spacing them evenly to allow proper heat circulation.
07 - Bake for 30 to 35 minutes, or until chicken is cooked through and internal temperature reaches 165°F. Tops should be golden brown and cheese should be bubbly.
08 - Carefully remove toothpicks before serving. Garnish with additional chopped parsley if desired. Serve immediately while hot.