Preheat the oven to 400°F / 200°C.
Mix together the grated parmesan, breadcrumbs, onion powder and Italian seasoning. In a separate bowl mix together the buttermilk and eggs.
Pat the chicken breasts dry then season with salt and pepper.
Take each chicken breast and dip into the egg and buttermilk mixture then coat in the breadcrumbs mixture then lay onto a baking sheet.
Bake for around 20-25 minutes until the breadcrumbs golden.
Remove from the oven and pour the marinara sauce around the chicken and down the center then top with the shredded mozzarella.
Place back into the over for another 10-15 minutes until completely cooked through and the mozzarella has melted.
Serve with a generous portion of spaghetti and fresh basil.