Trim any large fat or silver skin from the steaks. Place a steak between two pieces of plastic wrap or in a large resealable bag and gently pound with a meat mallet or rolling pin until about 1/4 inch (0.6 cm) thick. Repeat with remaining steaks. Season both sides lightly with 1/2 teaspoon salt and 1/4 teaspoon black pepper.

Set up breading station

Place the flour on a shallow plate. In a bowl whisk together the eggs and milk until combined. On a third plate combine breadcrumbs, grated Parmesan, garlic powder, dried oregano, and the remaining 1/2 teaspoon salt and 1/4 teaspoon black pepper; mix thoroughly.

Bread the steaks

Working one at a time, dredge a steak in flour, shaking off excess. Dip into the egg mixture, allowing excess to drip, then press firmly into the breadcrumb mixture to fully coat both sides. Place breaded steaks on a wire rack or baking sheet while you finish the rest.

Fry the milanesas

Pour vegetable oil into a large skillet to a depth of about 1/8–1/4 inch and heat over medium-high until shimmering (about 350°F/175°C if using a thermometer). Fry each breaded steak 2–3 minutes per side, until golden brown and crisp. Do not overcrowd the pan; fry in batches if needed. Transfer cooked milanesas to a wire rack or paper towel-lined plate and keep warm in a low oven (200°F/95°C) while you prepare the topping.

Tomato topping & assembly

Prepare the tomato sauce

In a small saucepan heat 1 tablespoon olive oil over medium heat. Add minced garlic and sauté 20–30 seconds until fragrant but not browned. Add the tomato sauce, 1/4 teaspoon salt and 1/4 teaspoon sugar (if using). Stir and simmer gently 5 minutes to marry flavors. Tear or chop basil leaves roughly and stir in off heat, reserving a few leaves for garnish.

Assemble milanesa napolitana

Preheat the broiler (or oven to 450°F/230°C) and position an oven rack 6 inches from the heat. Place the fried milanesas on a rimmed baking sheet. Spoon about 2–3 tablespoons of the warm tomato sauce onto each steak, spreading to cover most of the surface. Top each with about 1 ounce (roughly) of mozzarella, arranging slices or a sprinkle of shredded cheese evenly. Sprinkle each with a little grated Parmesan.

Melt cheese and finish

Broil 2–4 minutes, watching closely, until the mozzarella is melted, bubbly and lightly golden at the edges. Alternatively bake for 6–8 minutes at 450°F/230°C until cheese melts. Remove from oven and let rest 1–2 minutes. Garnish with torn basil leaves and chopped parsley. Serve with lemon wedges on the side and optional mashed potatoes or fries.

Garnish & serving

Squeeze a little lemon juice over the milanesa just before eating if desired. Plate with chosen side (mashed potatoes or fries) and sprinkle extra grated Parmesan and parsley atop. Serve immediately while hot and crispy.