(500g) fresh tuna, in a single slab about 1½ inches thick
cracked black peppercorns
(30) ml basil oil
Shavings of pecorino Romano Cheese
Trim any dark areas off the tuna.
Spread both sides with a thin film of the mustard.
Combine the peppercorns and poppy seeds on a flat plate and press them onto the tuna on both sides.
Wrap up the coated tuna smoothly in a sheet of foil.
Heat a heavy nonstick pan over medium heat.
Place the slab of tuna still wrapped in the foil in the pan and cook for 1½ minutes on one side. Turn it over and cook it for 1 minute on the other side.
Remove it from the pan.
Refrigerate the tuna until 1 hour before serving.
Place it in the freezer for 1 hour to make it easier to slice.
To serve remove the foil, cut the tuna into slices about ¼ inch (6mm) thick, and arrange them on 4 plates.
Drizzle with basil oil and serve garnished with lemon wedges and, if desired, some pecorino cheese.
When buying tuna look for rich rosy fish that is moist but not wet, with no signs of drying around the edges or cracking on the surface.