Roast beef with a mustard crust

Roast beef with a mustard crust
  • Serves: 6
  • Prep time: 10
  • Cook time: 60+ minutes
  • Ready in: Over 60 Minutes
  • Difficulty Rating: 1
  • Syns per serving:

This gorgeous roast is sure to be a Sunday favourite.


  • 1.5kg sirloin of beef, visible fat removed
  • 1 tbsp English mustard powder mixed with 1 tbsp water
  • 4 tbsp tomato purée
  • 6-8 tbsp mixed peppercorns, crushed
  • rosemary sprigs, to garnish (optional)


  1. Preheat the oven to 190°C/Fan 170°C/Gas 5.
  2. Put the beef in a roasting tin. Mix the made-up mustard and tomato purée and spread over the joint. Sprinkle over the peppercorns to form an even crust.
  3. Put the joint in the oven and cook to your liking (22 minutes per 500g plus an extra 20 minutes for rare; 28 minutes per 500g plus an extra 25 minutes for medium; and 33 minutes per 500g plus an extra 30 minutes for well done – so a 1.5kg joint cooked to medium needs 1 hour 50 minutes).
  4. Baste occasionally with the meat juices while roasting, and turn halfway through the cooking time.
  5. Once cooked, put the beef on a serving dish, cover loosely with foil and leave to rest for 15-20 minutes.
  6. Garnish with rosemary sprigs if you like, then carve and serve with your favourite potatoes and vegetables.

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