For the lamb
When ordering the saddle of Scotch Lamb, ask your butcher to remove the back bone, leaving the two eyes of meat attached to the fat. It is also necessary to ask him to remove the bark, which is a fine membrane covering the fat. Ask him to cut the bone and give you the trimmings for your sauce.
Remove any sinew and excess fat from the eye of the meat. Season with mill pepper. Chill and retain.
For the stuffing
Finely chop the shallots and sweat with the garlic. Slice and fry the black pudding on both sides, add to the shallots with the apple purée and mix well. Then add the breadcrumbs and mix into a smooth stuffing; season and allow to cool.
Once cool, remove the saddle from the fridge and fill the space in between the two trimmed loins on the saddle with the stuffing. Cover with the excess fat; roll up and secure with string.
Heat the oil in a frying pan and brown both trimmings and bones. Place in a large heated pot and continue to colour. Repeat this process with the mirepoix of vegetables. Add to the trimmings and continue to cook until caramelised. Add the red wine, reduce and caramelise further. Add the stock, herbs and cook down by half.
For the potato and vegetable purée
Quarter the potatoes and place in boiling water; season and cook until tender. Strain and check seasoning. Add butter and cream and beat until smooth. Keep warm. Place the carrot and onion trimmings into a pan, barely cover with stock, cover with a tight-fitting lid and cook until tender. Remove the lid and cook until all the stock has evaporated. Place in a processor and blend until smooth. Add two large spoons of the potato purée to bind; check the seasoning and keep warm.
For the hotchpotch
Wash the barley well and blanch for 5 minutes. Refresh and retain. Peel and wash the carrot and turnip; remove skins from the baby onions and wash. Cut the carrot into large dice, roughly 0.5cm, retain the trimmings. Cut the turnip into small batons and retain the trimmings. Partially cook the carrot in a little chicken stock. Remove and add the turnip, one teaspoon of honey and a pinch of saffron, remove and allow to steam dry. Place both the carrot and the turnips in a little casserole pan with a lid. Lightly colour the onions, adding a pinch of thyme. Place in the casserole; add the barley and enough lamb stock to cover.
Cover with a lid and cook until tender. Finally, add the spring onions which should be poached in a little stock until a slight bite. Remove and while warm, tie in a knot. Add to the hotchpotch, mix in and season.
Season the saddle of lamb and place on a bed of root vegetables. Roast in a preheated oven at 180°C/350°F/Gas mark 4 for about 30 minutes. Using a temperature probe, check the internal temperature which should be cooked until 55-60°C for a nice pink middle; then allow to rest for 15 minutes. Carve a nice thick slice of the lamb allowing to drain for 2 minutes. Meanwhile, spoon a small portion of the hotchpotch to the centre of the plate, rest the lamb on top. Using two spoons, add a quenelle of the potato and vegetable purée and surround with the vegetables and sauce.