Place the beef cutlets between two sheets of plastic wrap and gently pound them with a meat mallet until they are about 1/8 inch thick.
Season both sides of the cutlets with salt and black pepper.
In a shallow dish, place the flour.
In another shallow dish, whisk together the eggs and milk.
In a third shallow dish, combine the breadcrumbs, grated Parmesan cheese (if using), and dried oregano (if using).
Dredge each beef cutlet in the flour, shaking off any excess.
Dip the cutlet into the egg mixture, allowing any excess to drip off.
Coat the cutlet in the breadcrumb mixture, pressing gently to ensure the breadcrumbs adhere well.
Place the breaded cutlets on a plate and let them rest for about 10 minutes to set the coating.
In a large skillet, heat about 1/4 inch of vegetable oil over medium-high heat until hot.
Carefully add the breaded cutlets to the hot oil, working in batches if necessary to avoid overcrowding the pan.
Fry the milanesas for about 3-4 minutes per side, or until they are golden brown and crispy.
Use a slotted spoon to transfer the fried cutlets to a paper towel-lined plate to drain any excess oil.
Enjoy your meal!