Combine all of the ingredients for the crust, except the breadcrumbs, in a food processor and blitz until smooth. Set aside 4 tablespoons of the sauce then add the breadcrumbs to the remainder. Drizzle the lamb with olive oil and season with salt and pepper. Heat a large frying pan over a high heat, add the lamb racks and sear for 3 to 4 minutes until golden brown all over. Remove from the pan and set aside to cool. Preheat the oven to 200°C.
Lay the lamb on a roasting tray and pack the crust mixture over the meat. Roast for 8 to 10 minutes then transfer to a warm plate to rest.
Meanwhile, parboil the potatoes in a large pan of salted boiling water for 5 minutes then drain thoroughly. Heat a little olive oil in a large sauté pan, add the potatoes and fry for 5 minutes until golden. Add the butter and garlic and cook for 2 to 3 minutes until the garlic has started to soften. Add the chorizo and cook for 7 to 8 minutes until the potatoes are cooked through and the chorizo is crisp.
Blanch the asparagus in a large pan of salted boiling water for 2 to 3 minutes then drain thoroughly. Drizzle with the balsamic glaze and a little olive oil and sprinkle with the Parmesan. Carve the lamb into the cutlets and serve with the potatoes, asparagus and reserved sauce.