8 skinless, boneless, chicken breast halves
3 eggs, beaten
4 cups parmesan bread crumbs
1 cup all-purpose flour, or more if needed
1 cup vegetable oil for frying
1 qt jar homemade spaghetti sauce
1 pkg shredded mozzarella cheese
1 cup grated provolone cheese
1 cup grated parmesan cheese
Preheat an oven to 450 degrees F (230 degrees C).
Place chicken breasts between two sheets of heavy plastic (resealable freezer bags work well) on a solid, level surface. Pound chicken with the smooth side of a meat mallet to a thickness of 1/2-inch.
Beat eggs in a bowl and set aside. Coat both sides of chicken with flour. Dip flour-coated chicken breast in beaten eggs. Transfer breast to bread crumb mixture, pressing the crumbs into both sides. Repeat for each breast.
Heat 2 cups oil in a large skillet on medium-high heat. Cook chicken until golden, about 2 minutes on each side.
Place chicken in a large baking dish and top each breast with about 1 cup of sauce. Layer each chicken breast with equal amounts of mozzarella cheese. Sprinkle 2 to 4 tablespoons of parmesan cheese on top and drizzle with 1 tablespoon olive oil. Bake in the preheated oven until cheese is browned and bubbly, and chicken breasts are no longer pink in the center, 15 to 20 minutes.
Serve on top of one cup or more of spaghetti cooked al dente.