Light the grill and wait until charcoal is red in an area larger than the steak.

Place the steak directly on the red hot charcoal. After around 2.5 mins turn the steak and leave for another 2.5 mins. Check the core temperature Remove steak when core temp reaches 104-122F for a medium finish at 135F.

Smear the surface with the rosemary baste and wrap in foil. Leave to rest for at least 10 mins.

Slice across the grain and serve.