Preheat oven to 400 F. In a shallow dish, whisk together egg and milk. In another shallow dish, combine breadcrumbs, grated parmesan cheese and Italian seasoning.
Coat chicken in the egg mixture, letting the excess drip off. Fully coat chicken into the breadcrumb mixture.
Place chicken onto a greased baking sheet. Bake for 30-35 minutes. Top each chicken with 2 tablespoons of marinara sauce and mozzarella cheese. Bake for another 5 minutes, until the cheese is melted.