- Peel potatoes and cut into even sizes, boil in salted water until soft, drain and mash through a potato ricer or by hand.
- Beat in 150g unsalted butter and season with salt. Allow to cool to room temperature.
- For each of the four pies, mould the potato into a sausage shape and place in the middle of a sheet of pastry. Brush pastry with egg yolk and roll into a tight cylinder, roll up the edges with more egg and then chill it in the fridge.
- Preheat the oven to 190°C/ fan 170°C/Gas 5. Heat a frying pan and add a little oil, seal the lamb on all sides until it is golden brown, on a medium to high heat.
- Add the garlic, herbs and butter and transfer everything to a roasting tin. Cook for 15-20 minutes. The meat should feel rare.
- Remove from oven and baste with pan juices, season. Allow it to rest for at least 10 minutes.
- Take 2 tablespoons of lamb cooking juices and combine with the reduced chicken stock, season with salt and a little lemon juice.
- With a knife carefully shave the outer florets of cauliflower and finely chop (it should look like cous cous).
- Cook in a little olive oil over a medium heat for 2 minutes. Allow it to cool, then add nuts, parmesan, garlic, olive oil, lemon zest and season with freshly milled black pepper, salt and lemon juice.
- Deep fry the cauliflower florets in vegetable oil at 180°C until they are golden brown. Season them and dry them on a paper towel.
- To serve - deep fry the potato pies until they are golden brown, carefully cut the ends off with a serrated knife and then cut in half to achieve 2 small cylinders.
- Spoon the pesto on to the plate, add the potato pies, then carve the lamb rack into cutlets and alternate with fried cauliflower. Finish with the lamb cooking juices.