Slow-roasted rib of beef with bone-marrow sauce

Ingrediënten

• Groundnut oil
• 1 well-aged three-bone rib of beef (on the bone)
• Salt
• 2kg beef stock (p.40)
• 100g unsalted butter
• 250g peeled and finely sliced shallot (approx. 5 banana shallots)
• 150g white wine
• 100g dijon mustard
• 10g sherry vinegar
• 15g lemon juice
• 100g bone marrow, rinsed and diced (ask the butcher)
• 20g flat-leaf parsley leaves
• 20g chives
• 10g tarragon leaves
• Salt and black pepper