I made this roasted rack of lamb with a herb crust and rosemary jus yesterday and it was really good. If you want to make it, here is the recipe which is from BBC food. I would recommend using less breadcrumbs than suggested in the recipe as I has too much of the bread crumb and herb mixture left over. As I tend to try and use everything to prevent waste I have saved the remaining left over herb crust mixture and intend to use it to make a herb crusted chicken breast during the week.
For the herb crust
200g/7oz fresh, rich white bread
2 tbsps freshly chopped flat leaf parsley
1 tsp fresh soft thyme leaves
1 tsp fresh rosemary leaves
1 fat garlic clove, peeled and finely chopped
4 tbsp vegetable oil
100g/4oz unsalted butter
sea salt and freshly ground black pepper
2 tbsp Dijon mustard
2 lean racks of lamb, french trimmed
For the rosemary jus
500ml/17fl oz hot, good lamb stock
1 large sprig fresh rosemary
1. Preheat the oven to 240C/450F/Gas 9.
2. To prepare the herb crust, break the bread into large pieces and place in a food processor or blender and turn into fine crumbs.
3. Add the herbs and garlic and blitz for a further 30 seconds.
4. Heat the oil in a large pan with the butter until foaming, but not coloured. Season the racks and add to the pan, skin-side down, and cook for 3-4 minutes on each side (for medium rare). Remove from the pan and leave to rest for 5 minutes.
5. Place the racks of lamb, fat side up, on a chopping board, and brush the mustard over the racks, to apply a good coating.
6. Press a generous handful of the herb crust over the racks and transfer to a medium-sized roasting tin and roast for 5-15 minutes, depending on how your lamb is preferred. Cover the bones with foil if browning too quickly.
7. To make the jus, heat the stock and rosemary in a pan over a medium to high heat and reduce by half, stirring occasionally. Check seasoning, strain and keep warm.
8. Slice the racks in half and serve immediately.