Remove joint from its packaging the night before cooking and dry with kitchen paper. Chill overnight.
Preheat the oven to gas 7, 220ºC, fan 200ºC. Mix the breadcrumbs, anchovies, herbs and garlic together with the olive oil, and season well.
Remove the string and unroll the beef. Press the stuffing down and roll the joint up again, using the string to tie it back together. Sprinkle the top layer of fat with sea salt.
Put in a roasting tray and cook for 25 mins. Then reduce the oven temperature to gas 3, 160ºC, fan 140ºC and cook for another 42 mins for rare (53 mins for medium, 63 mins for well done).
Remove and allow to rest for 20 minutes, lightly covered in foil.
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For top tips on protecting you and your family when preparing raw meat and poultry, visit Food Safety in the Home.