Step 1

Lay the chicken breasts in the slow cooker.  Mix the garlic powder, salt, pepper, and Italian seasoning mix together in a small bowl.  Sprinkle the mixture evenly over the chicken breasts, patting lightly so it will stick to the chicken.

Step 2

Sprinkle the Parmesan cheese evenly over the chicken, then pour the marinara sauce on top, covering the tops and sides of the chicken.

Step 3

Cover and cook on low, checking after 3 1/2 hours.  (Or cook on high, checking after 1 1/2 hrs.)

Step 4

Uncover and sprinkle the mozzarella evenly over the chicken.  Cover and cook on low for about 15 more minutes, until cheese is completely melted.