Mustard-infused rib-eye with crispy potatoes

For the marinade, combine the wine, oil, mustard, salt, pepper, shallots, garlic, chilli, tarragon and parsley. Mix thoroughly before covering the steaks completely in the marinade. Place in the fridge and leave for 24 hours

1 hour before you cook the steak, peel and wash the potatoes. Cut into even chunks and place in a large pan, cover with cold water. Add 4 large pinches of salt and bring to a gentle boil

Cook until tender but still slightly firm in the centre, approximately 8-10 minutes. Drain the water and toss in the colander to gently break up edges. Leave in the colander to steam for a few minutes

Place a heavy-based roasting pan over a high heat. Add the duck fat and melt until hot. Place the potatoes in the hot duck fat and turn evenly to give each piece a crispy, golden brown finish

Transfer the potatoes to an oven set to 220°C/gas mark 8 and roast for a further 15-20 minutes. Once cooked, remove and keep warm

Turn the oven down to 200˚C/gas mark 6. Place a pan over a high heat and add a splash of vegetable oil

Add the steaks and cook until the meat is a dark brown colour, turn over and to cook the other side until a similar colour is achieved

For a rare steak, you do not need to cook the steak further in the oven. For a medium-rare steak, place in the preheated oven for 1 minute (increase this number by 2 minute increments for medium, medium-well and well-done finishes). Remove the steaks from the oven and set aside to rest for 4 minutes. Serve with the potatoes and mustards