Perfect Roast Dry Aged Sirloin of Beef

Ingredients

Serves: 4-6

• 1.5kg Sirloin of Beef
• Rapeseed oil
• 2 medium onions (optional)
• A few sprigs of thyme (optional)
• Salt
• Freshly ground black pepper
• 6 tbsp Potts Hot Horseradish and Chilli Mustard Sauce, to finish

Method:

Cooks in: 2 hours • Difficulty: Medium

1. Preheat the oven to 220°C/200°C fan/Gas mark 7.
2. Take the beef out of the fridge and place it in a cool place for at least an hour and a half before cooking, allowing it to come to room temperature.
3. Once the beef has reached room temperature rub the beef all over with plenty of rapeseed oil and season with salt and black pepper. Peel and thickly slice the onions and place them in a heavy roasting tin with the sprigs of thyme (if using). Put the meat on top of the onions and roast in the preheated oven for 30 minutes.
4. Turn the oven down to 160°C/150°C fan/Gas mark 3 and roast for a further 10 minutes per 500g for rare, or 12 minutes per 500g for medium-rare, or 15 minutes per 500g for cooked through. You can test the meat with a meat thermometer if you have one - it should read 50°C for rare meat.
5. 30 mins before the end of cooking time, spread the horseradish and chilli mustard sauce on top of the meat, baste well and return to the oven.
6. Remove the roasting tin from the oven and leave the meat to rest for 15-20 minutes in a warm place, loosely covered with foil but not completely sealed or the meat will steam.
7. Carve the roast beef and serve on a warm platter.