Place veal cutlets between two sheets of plastic wrap and pound with a meat mallet or rolling pin until each is about 5 mm thick and even across the surface.

Season both sides with salt and pepper. Spread the flour in a shallow bowl and dredge each cutlet, pressing lightly so the flour adheres, then shaking off the excess.

Heat a 12-inch skillet over medium-high heat. Add the olive oil and 30 g of butter and let the butter foam subside before adding any meat.

Working in batches, lay 2 to 3 cutlets flat in the pan without overlapping. Sear for 1.5 to 2 minutes per side until golden and cooked through. Transfer to a warm plate and repeat with the remaining cutlets.

With the skillet still over medium-high heat, pour in the white wine and scrape up any browned bits from the base. Let it reduce by half, about 1 minute.

Add the chicken stock and simmer for 1 minute until slightly reduced. Remove the pan from the heat.

Pour in the lemon juice (and zest if using) and swirl the pan. Add the remaining 30 g of cold butter in small cubes and swirl continuously off the heat until the sauce is smooth and glossy.

Taste and adjust salt. Return all cutlets to the pan for 20 seconds, spooning the sauce over them to coat.

Arrange the cutlets on warmed plates, spoon the pan sauce over the top, and scatter chopped parsley over each portion. Lay a lemon slice on the side and serve immediately.