This Is a great dish to eat on easter Sunday. I recommend making the dauphinoise potatoes a day before as your oven is going to be at 80°C for 3-4 hours on the day of cooking the lamb. You can always reheat the dauphinoise potatoes in the oven while your lamb is resting.
For the lamb
1.7kilo leg of lamb
2 celery sticks
5 cloves garlic
For the bone marrow sauce
1000ml beef stock
50g unsalted butter
75ml white wine
50g dijon mustard
5ml sherry vinegar
7ml lemon juice
50g Bone marrow, rinsed and diced (ask the butcher)
5 clove garlic crushed
4 bay leaves
440ml double cream
For the lamb
1. Pre-heat your oven to 80°C and season the lamb with salt.
2. Roughly cut the vegetables and make a bed in a roasting tray then add the garlic and rosemary.
3. Heat the oil in a heavy frying pan over a high heat. When the oil is smoking hot, add the lamb and sear until golden brown on all sides. Remove the lamb from the pan and place in the roasting tray. De-glaze your pan with a glass of white wine then pour over the lamb.
4. Cook for approximately 3 1/2 hours. When cooked remove the lamb from the oven, wrap it in foil and allow to rest for 30 minutes. (making sure you can capture the resting juices)
5. Strain what's left in the roasting tray and put the juices to the side to set. (you will need to separate the fat from the juices)
For the sauce
1. Pour the beef stock into a large saucepan and place over a high heat. Bring to the boil and allow the liquid to reduce by three-quarters.
2. While the stock is reducing, melt the butter in a saucepan and cook the shallots until they are light brown colour. Add the wine and allow to reduce by three-quarters.
3. Remove the shallot pan from the heat and add the dijon mustard. Stir thoroughly before adding the reduced beef stock.
4. Add the sherry vinegar and lemon juice and whisk until all the ingredients are fully incorporated.
5. Gently heat the sauce and when hot, add the diced bone marrow and remove from the heat. Th bone marrow should soften but not melt.
6. Stir in the juices from the roasting tray. Finely chop the herbs and stir them into the sauce. Season with salt and pepper.
For the dauphinoise potatoes
1. Pre-heat your oven to 180°C
2.Heat some oil in a saucepan and add the crushed garlic. Fry for 2 minutes then add the cream and bay leaves. Season with salt and pepper. Bring to the boil then turn off the heat.
3. Peel and slice the potatoes and layer in an oven dish. (sprinkling the chopped garlic and a little salt on top of each layer).
4. Once you have run out of potato, pour over the cream mixture and then push the potatoes down so it's completely covered. Cover with foil and cook for 1 1/2 hours. (removing the foil after 1 hour of cooking)
Serve with asparagus. I think the best way to cook asparagus is to fry in a generous amount of butter and a splash off water over a medium heat for about 6-7 minutes.
Hope you enjoy this dish and eat plenty of easter eggs :)