Toast each slice of bread in toaster until crispy and dark brown, allow to cool. Break into smaller pieces and blend in a food processer with ½ tsp salt and ½ tsp pepper until you have finely milled breadcrumbs.
Preheat oven to 400 degrees F.
Combine the breadcrumbs, garlic powder, Parmesan cheese, remaining salt and pepper, and Italian seasoning in a shallow dish.
Beat eggs in a separate shallow dish and dip in each chicken breast, submerging fully.
Dredge chicken breasts through the breadcrumb mixture until thoroughly coated on both sides.
Place chicken breasts on a lined baking sheet and brush lightly with olive oil. Bake 15-20 minutes.
Turn chicken breasts over and top each with ½ cup of Marinara sauce and ¼ cup Mozzarella cheese. Bake 5-10 more minutes and let cool.
