Start with the chips. First, heat the vegetable oil in an electric deep-fat fryer to 160°C/325°F (if you don’t have a deep-fat fryer see Frying Notes, below) and heat your oven to its lowest setting. While the oil is heating, peel the potatoes and cut into chips roughly 5cm by 1cm and place into a bowl of cold water until ready for cooking, but don’t leave any longer than 10 minutes. Get all your frying equipment together and line a colander with several layers of kitchen paper for draining the chips once fried.
Drain and rinse the chips in another colander. Tip onto a clean tea towel and carefully pat them dry. Tip half the chips into the basket of the fryer; too many in at once will stick together. Fry for 7-8 minutes until soft and not at all coloured. Lift out of the oil and drain on the prepared kitchen paper. Allow the oil to come back to temperature, fry the remaining chips, drain and set aside.
Now cook the steaks. Place a large heavy frying pan on a high heat. Season the steaks well with the Maldon salt and freshly ground black pepper. Add the sunflower oil to the hot pan. When it starts to smoke add the steaks. It’s important to leave the steaks and resist the temptation to move them around.
After 2-3 minutes blood will start to appear on the top, they're now ready to turn. Cook on the other side for another 2-3 minutes. Add the butter, garlic and thyme at this point and allow the butter to foam. If your steaks have a particularly fatty edge, use tongs to hold each steak on its side and press the fatty edge into the pan to colour. A meat thermometer is a great tool for steaks - in the pan, the core temperature of the steaks should be 35°C to 40°C for rare. (See Nick’s Notes, below, for steak temperatures.)
Remove the steaks and place on a metal tray in a warm, not hot, place to rest for 4-5 minutes. The temperature of the steaks will actually rise as they rest. At 48°C rare steaks are ready to eat.
When you set the meat aside to rest, get back to the chips. Reheat the oil to 180°C (190°C for really puffy chips) and fry the chips in 2 batches for a couple of minutes until light golden brown and crisp. Drain them on kitchen paper. Sprinkle with a little Maldon sea salt. Do not cover the chips or they will lose their crispness. If keeping warm for a few minutes, spread them on a baking tray lined with kitchen paper in the warm oven, leaving the door ajar to let any steam escape and keep them crisp. Serve immediately.
Place the steaks on warm plates with the chips and watercress on the side. Pour a glass of gutsy, fruity red wine and enjoy!
Nick’s notes: If you don’t have an electric deep-fat fryer, use a wok because the sloping sides allows the hot oil to bubble up without bubbling over. A spider spoon is an essential tool as it will allow you to manoeuvre larger amounts of food at a time and also move food around to prevent it sticking together. Always drain food on kitchen paper.
Only fill a wok to 1/3 capacity and a fryer to half full. Use a cube of bread to check the oil temperature. On a low heat (160°C) a cube will take 60 seconds to brown, 40 seconds on a medium heat (180°C) or 20 seconds on a very high heat (190°C).
The trick with steak is not to overcook it. The temperature of the meat while cooking should reach 35°C for rare, 40°C for medium rare, 45°C for medium, 50°C for medium to well done, and 65°C for well done. The temperature on the thermometer will change, but you’re after the lowest point.
It’s also crucial to let steak rest until all the juices have had a chance to redistribute throughout the meat. People think it will go cold in the 5 or 6 minutes it’s left, but in fact, the meat climbs in temperature while it’s resting. At 48°C you’re ready to serve. For a great steak like this, you don’t need anything else. Fancy sauces will detract from the flavour of the meat and it will be juicy enough on its own.