Roast rib of beef with mustard-seed crust

Method

1. Preheat the oven to 230°C/fan 210°C/gas 8. Weigh the beef and calculate the cooking time, allowing 15 minutes per 500g for medium-rare. Spread the onion, celery and carrots over the centre of a large roasting tin. Rub the joint all over with a little oil and season the cut faces with salt and pepper. Score the fat in a diamond pattern with a sharp knife, then season lightly and spread with the Dijon mustard. Mix the flour with the mustard powder, pepper, crushed mustard seeds and salt, then pat firmly onto the fat. Sit the joint upright on top of the veg, taking care not to knock off the crust, then roast on the top shelf of the oven for 20 minutes. Move to a lower shelf, turn down the oven to 170°C/fan150°C/gas 3½, then roast for the rest of the cooking time – 1 hour 10 minutes for a 3kg piece of beef.
2. After the beef has cooked for 1 hour, make the Yorkshire pudding batter. Blend the ingredients except the dripping, plus 150ml water, in a liquidiser until smooth. Set aside for 30 minutes.
3. Remove the cooked beef from the oven and lift onto a carving board. Turn up the oven to 220°C/fan200°C/ gas 7. Cover the beef with foil, then rest for 30 minutes. Pour the fat from the roasting tin into a bowl and make up to 2 tbsp with melted beef dripping or lard if need be. Spoon ½ tsp of this fat into each hole of a 12-hole muffin tray. Heat on the top shelf of the oven for 5 minutes until sizzling, then remove carefully and fill each hole three-quarters full with batter. Return to the oven, making sure there’s room for the Yorkshires to rise, then cook for 25-30 minutes until puffed, crisp and golden.
4. Meanwhile, make the gravy. Put the beef-roasting tin directly over a medium heat on the hob. When it’s sizzling hot, stir in the flour. Add a little of the stock and scrape the base of the tin with a wooden spoon to release all the cooking juices, then gradually add the rest of the stock, along with the wine and port. Bring to a boil, lower the heat and simmer for 15 minutes until reduced and well-flavoured. Strain into a clean pan, taste, season and keep hot.
5. Uncover the beef and pour any juices from the carving tray into the gravy. Carve the beef into thin slices and serve with the Yorkshire puddings and gravy.