Step 1

Warm a serving plate. Heat a heavy frying pan (preferably carbon steel or stainless steel) over medium-high heat until very hot. Season the steak generously with salt and pepper, then add the oil to the pan. Cook the steak to your liking (see tips below), and about 2 minutes before the steak is likely to be done, add the butter and spoon it over the steak repeatedly until the steak is cooked. Remove the steak from the pan and set aside on the warm serving plate to rest.

Step 2

To make the pan jus, return the pan to the heat and add a third of the butter for the pan jus. Add the eschalot, garlic, thyme and any parsley stems, and fry for about a minute until fragrant. Add the red wine, stock and gelatine (if using) and scrape up any brown bits from the base of the pan. Simmer until the liquid has reduced by about two-thirds. Pour in any resting juices from the steak. Whisk in the remaining cold butter, add a dash of vinegar, then strain the sauce into a warm jug or bowl.

Step 3

Wipe out the pan and return it to the heat. Add a touch more oil then flash the steak for 30 seconds on each side to refresh it. Slice the steak and pour the reserved pan jus onto the serving plate. Place the steak on top and serve scattered with a little parsley.