1
Start with preparing your shoestring fries. Slice the potatoes thinly on a mandolin and then roll your knife through them to create thin matchstick length chips. Wash the potato in iced water to remove excess starch and then dry thoroughly on a cloth. Set aside in the fridge on the cloth to continue drying until cooking.
2
Now for the steaks. Heat a non-stick frying pan until it is smoking hot, then add the oil. Season the steaks liberally with sea salt then brown on all sides in the pan.
3
Now reduce the heat slightly and keep turning the steaks every 30 seconds. Use a metal skewer to check the internal temperature of the steak: when medium rare, the skewer should be warm to touch (if you have a meat thermometer, aim for approximately 46 degrees for medium rare). Remove the steaks and rest them for 5 minutes on a plate.
4
While the steaks are resting, pour the cognac into the pan (be careful if using a gas hob as the cognac can briefly ignite). Next, add the black pepper and cook out for a minute until the liquid has almost evaporated. Then add the cream and stock and reduce by half before adding the green peppercorns. Cook over a high heat for 2 minutes until a thick sauce-like consistency has formed.
5
Now return the steaks to the pan, along with all the resting juices from the plate. Coat the steaks in the sauce, season with a touch of lemon juice, and serve warm.
6
To cook the shoestring fries, place the oil in a heavy based pan and heat to approx. 170c. Add the fries, in batches, and keep moving in the oil using a slotted spoon for 2 to 3 mins until evenly golden brown. Remove and dry on paper and season with salt. Serve these on top of the steaks.