“With this recipe I want to show you how to cook a really luxurious cut of beef in the perfect way. And to go with it, I’ve given you the most mind-blowing roast potatoes you’ll ever taste – I squash the spuds to get extra surface area for crispiness, then spritz them with a homemade flavoured vinegar for an amazing added hit of flavour. ”
Get the meat out of the fridge and up to room temperature before you cook it. Preheat the oven to 200ºC/400ºF/gas 6 and place a large roasting tray inside to heat up.
Peel the potatoes, halving any larger ones, then parboil in a pan of boiling salted water for around 12 minutes. Drain, chuff up and leave to steam dry while you separate and bash the unpeeled garlic cloves.
Carefully remove the hot tray from the oven and drizzle in 1 tablespoon of olive oil, then add the butter, rosemary sprigs and garlic, followed by the potatoes. Gently toss to coat, then season with sea salt and roast for 45 minutes to 1 hour, or until beautifully golden and crisp.
Meanwhile, put your chosen flavoured vinegar ingredients into a small water spritzer and set aside. Make a herb brush by tying the woody herbs to the end of a wooden spoon with string.
Put a large ovenproof frying pan on a high heat to get nice and hot. Drizzle in 1 tablespoon of olive oil, season the steak well and add to the pan, fat side down. Leave for a few minutes so the fat renders out.
Now sear for around 8 minutes, or until browned all over, turning and basting with the herb brush every minute or so.
Transfer the pan to the oven for 15 minutes for medium, or until cooked to your liking, turning halfway. Move the steak to a board, drizzle with the pan juices and leave to rest.
A few minutes before the roast potatoes are ready, spritz them with the flavoured vinegar – not too much, you want it to be subtle. Return them to the oven for 30 seconds, then lightly squash them with a fish slice. Spritz again and return to the oven for a final few minutes.
Slice up the steak and sprinkle with a little salt. Mix a splash of extra virgin olive oil into the resting juices, then drizzle over the steak. Serve with the vinegary roasties. I like to have a good pinch of watercress and a dollop of mustard on the side, too.