Cast Iron skillet (the kind you'd smash eddie or richie with in Bottom) and heat the living daylights out of it, then cook. next best thing to firing the BBQ up
Add a few Jack Daniels smoking chips to a square iron skillet (like they have at Ikea) it and get it mega hot, drop the steak in and cover with a round frying pan (i.e leaving a 4 corners uncovered to let it vent (otherwise it will take on a rather weird texture).
Or add a few drops of good quality soy sauce before dropping the steak in and allow that to flavour the steak.
However I am sure both Techie & Fabrice will have something to say on both matters.