Place the beef in the freezer for 20–30 minutes until very firm but not frozen solid; this makes slicing thinly much easier. Using a sharp knife, slice the beef as thinly as possible (aim for almost translucent). If desired, arrange slices between two sheets of plastic wrap and gently pound with a meat mallet or rolling pin to flatten to about 1–2 mm thickness.

Arrange the thin beef slices in a single overlapping layer on a chilled large plate or platter. Lightly season the arranged slices with the kosher salt and freshly ground black pepper, distributing evenly.

Dressing & finishing

Make the dressing

In a small bowl, whisk together the lemon juice, Dijon mustard and a pinch of salt. Slowly whisk in the extra-virgin olive oil until emulsified. Stir in the rinsed capers and chopped parsley.

Drizzle about two-thirds of the dressing evenly over the beef slices, using the remaining dressing to lightly dress the optional arugula if using. Scatter the arugula on top or to the side of the beef as desired.

Using a vegetable peeler, shave Parmesan directly over the beef in long thin ribbons until you have about 1/2 cup of shavings distributed across the carpaccio.

If desired, finish with a small extra drizzle of olive oil and a final grind of black pepper. Garnish with the toasted baguette slices on the side and serve immediately.

Optional accompaniment

Toast thin baguette slices until golden and crisp. Serve alongside the carpaccio for spreading or eating with the beef and Parmesan shavings.