For the breast; Remove ribs from the breast (most butchers or farm shops will do this for you), trim off any excess fat, season and roll tightly into a sausage shape in cling film, tie each end. Place in a slow cooker or oven proof dish and cover with water, add a spring of Rosemary and garlic, cover and cook overnight (approx 10-12 hours). Remove from liquid, allow to cool, then re-roll and chill. (save the poaching liquid for later use).
For the Sweetbreads; Place the breads in a pan & cover with milk, add thyme, gently bring to the boil and simmer for 5 minutes, plunge in cold water (this stops them overcooking), peel any fat or sinew off.
For the carrot puree; Place the peeled & chopped carrots in a pan add enough poaching liquor to cover then boil until tender, place in a food processer and blitz until smooth, add butter and season to taste.
For the Chantilly carrots; Put carrots into a pan, cover with the poaching liquid, cook until tender.
For the Savoy; Put the thinly chopped cabbage into a pan, with butter, salt and pepper, gently fry until soft .
To serve; portion the chilled breast into 4 equal pieces in an oven proof pan, fry each side to seal then add the carrots and sweetbreads, place the entire pan in pre heated oven for approx 10 minutes, meanwhile heat the puree and cabbage (pan or microwave is fine). Place the puree on 1 side of the plate, place breast on top, pile up cabbage next to the lamb, place on top sweetbreads and Chantilly, serve with Rosemary and Henderson's relish gravy