Pound the beef cutlets on both sides with a meat mallet until they are thinner and more tender. Season with oregano, garlic, salt, and pepper. Dredge the cutlets in flour, then dip in the beaten egg, and coat with breadcrumbs. Fry in oil until golden brown.

Place the fried milanesa on a baking sheet. Top with tomato sauce, slices of mozzarella cheese, and grated Parmesan cheese. Bake until the cheese is melted. Slice the bread horizontally and spread tomato sauce on the bottom half. Add basil leaves and the milanesa. Serve with a salad if desired.