Preheat an outdoor barbecue to high heat. If using charcoal, keep the coals to one side, ensuring the other side of the barbecue is free of coals.
Pat your steak dry with kitchen paper, if necessary. Season to taste with salt and pepper, or use your favourite steak seasoning mix.
Place the steak on the BBQ. Flip after 45 seconds. After 45 seconds flip again, making sure to flip and turn the steak 45 degrees to get a nice criss-cross pattern from the cooking grate. Finally, flip again and cook for 45 seconds. (In short, you cook each side twice for 45 seconds each.)
Move the steak to the side of the BBQ without coals. Close the lid and cook to your desired doneness, checking the internal temperature with a meat thermometer. (See footnote for temperature guide.)
Steak temperature guide
Rare - 52 C
Medium rare - 54 C
Medium - 60 C
Medium well - 65 C
Well done - 70 C