For the potatoes, first put the garlic in a pan with the cream and bring to the boil. Strain out the garlic and season with salt and pepper. Next peel and slice the potatoes. Arrange on a greased oven dish and season between each layer and coat with the garlic cream after each layer. Cover and bake in the oven at 170°C for 30-40 mins until tender.
For the parsnip puree, peel and chop the parsnips. Put into a pot and cover with the cream. Cook until tender and puree in a blender until smooth. Season with salt, black pepper and mace and keep warm.
Wilt the spinach with a little salt and a dash of water. Strain the juices from it and set aside in warm place until ready to serve.
Portion the lamb in two (each person should get 3 bones each). Season and sear with a little oil on all sides until golden. Add the rosemary and some butter and then put in a hot oven at 170°C for 8 minutes. Then remove from the heat and let it rest in a warm place until ready to serve.
Make the herb crust by blending all the herbs with the butter and stock cube. Spread some of the mustard over the lamb then put some of the herb crust on top and place under the grill to heat up the meat.
For the sauce, put the lamb stock and redcurrants into a pot and reduce the liquied until it has a sauce consistency, add any juices from the meat, season and keep warm.
To serve, place some spinach on the plate. Carve the rack into chops and place on top. Put the purée to one side and spoon some redcurrent sauce over the meat.