To cook a perfect fillet steak, medium-rare, first get your heavy-based pan really hot. Gas is best for this in the kitchen. Lightly oil and season your steak, allowing it to get to room temperature. Don’t let the salt rest on your steak for more than a few minutes before cooking, though, as it draws out the moisture in the meat, although this can give a very nice ‘crust’ to the outside. Once your pan is really hot, place your steak in the pan. After four minutes, turn the steak over. After another three minutes, take the steak out and let it rest on a plate wrapped tightly in foil for a further 2-3 minutes.