If steaks are thicker than ~1/4 inch, place each between two sheets of plastic wrap and gently pound with a meat mallet until about 1/4" thick. Trim excess fat. Pat dry with paper towels. Season both sides evenly with 1 tsp salt and 1/2 tsp black pepper (from the beef ingredients).

Set up breading stations

Put flour in a shallow dish. In a second shallow bowl, whisk together the 3 eggs and 3 tbs milk until homogenous. In a third shallow bowl combine breadcrumbs, 1/2 cup grated Parmesan, 2 tbsp chopped parsley, garlic powder, paprika, remaining 1 tsp salt, and remaining black pepper; mix thoroughly.

Dredge and bread

Working one at a time, dredge each steak in flour shaking off excess, then dip into the egg wash, letting excess drip off, then press firmly into the breadcrumb mixture to coat evenly on both sides. Place breaded cutlets on a wire rack and let rest 10 minutes (this helps coating adhere).

Fry the milanesas

Heat a large skillet over medium-high heat. Add vegetable oil and butter (if using). When oil shimmers and registers ~350°F (175°C) or a breadcrumb sprinkled in sizzles immediately, add cutlets in a single layer without crowding (work in batches if necessary).

Fry each cutlet 2.5–3.5 minutes per side until golden brown and crisp. Adjust heat as needed to avoid burning; aim for an even deep-golden color. Transfer cooked cutlets to a baking sheet lined with paper towels or a wire rack to drain briefly. Keep warm in a low oven (200°F / 90°C) while finishing remaining cutlets.

Make the Napolitana sauce

In a small saucepan, heat 1 tbsp olive oil over medium heat. Add minced garlic and sauté 30–45 seconds until fragrant but not browned.

Add 2 cups tomato sauce (passata), 1 tsp dried oregano, 1/2 tsp salt, 1/4 tsp black pepper, and 1/2 tsp sugar if using. Stir and simmer gently 6–8 minutes to meld flavors and slightly thicken. Taste and adjust seasoning. Keep warm until ready to top the cutlets.

Assemble and melt

Preheat broiler to high with a rack about 5–6 inches from the heat source (or preheat oven to 450°F / 230°C if no broiler).

Place fried milanesas on a rimmed baking sheet. Spoon about 2–3 tablespoons of warm Napolitana sauce over each cutlet, spreading to an even thin layer but leaving edges of breading exposed so it stays crisp. Top each with about 1/3 cup shredded or sliced mozzarella and a light sprinkle of grated Parmesan.

Broil for 2–4 minutes, watching carefully, until cheese is melted, bubbling and lightly golden. If using a 450°F oven, bake 6–8 minutes until cheese melts and edges begin to brown.

Remove from oven. Garnish with torn fresh basil leaves and an extra dusting of Parmesan if desired. Serve immediately with lemon wedges and extra parsley or olive oil.