Remove the cote du boeuf from its packaging and leave to fully defrost, this will take about a day. Alternatively, place the steak in its plastic packaging into a sink full of cool water, it will thaw in just a couple of hours.
Once thawed, leave the steak out and allow it to come to room temperature.
Pat dry and generously season on both sides with salt and black pepper.
Place a cast iron pan over a medium-high heat and to the pan dollop in a little beef dripping or oil.
Once the fat is sizzling lay the steak into the pan, being careful not to move it.
After 3 minutes, or once the steak has built up a beautiful caramelised crust, flip it over onto the other side and cook for a further 3 minutes.
Reduce the heat so it’s more like medium than medium-high and cook for a further 4 minutes, turning the steak to the other side after each minute.
To the pan add a generous knob of butter and baste the steak with the foaming butter for a further 3-4 minutes.
When you touch the steak it should have a slight spring to it. Alternatively, use a meat thermometer and check the steak has reached 50C. This should cook your steak to a perfect medium/rare.
Leave to rest for at least 15 minutes before carving.