Preheat your oven to 220C.
First, rub the joint with the olive oil all over, then with the mustard.
Season well with salt and pepper all over.
Now put the joint into the preheated oven on 220C for 30 minutes.
After that time, turn the temperature down to 180C and open the oven door slightly for a few minutes to let out some of the surplus heat.
Roast for 12 minutes per 500g for a perfect pink.
After that time, take the beef out of the oven and cover with tinfoil.
Leave to rest for 15 minutes before serving.