Start by making the lamb. Heat your oven to 200°C/Fan 180°C/Gas 6. In a food processor mix together the pistachios, garlic, butter, breadcrumbs, 2 tablespoons of the mustard, lemon juice, parsley, thyme and mint.
Take your rack of lamb and score the skin, being careful not to go through the flesh. Scoring helps to render the fat and helps make the crust stick. Season on both sides generously with salt and pepper.
Heat a large ovenproof non-stick frying pan on a medium heat and brown your lamb fat side down for roughly 10 minutes until crispy. Flip the racks over and pop in the middle of the oven for 8 minutes.
After 8 minutes take the racks out of the oven. As fast as you can, spread a thin layer of the remaining wholegrain mustard over the skin then carefully pat down the crust so there is a firm even layer over each rack.
Pop back in the oven for 6 minutes for medium rare or 8 minutes for medium. Let the lamb rest for a few minutes before carving.
For the potatoes, cook in a pan of boiling water until a knife passes through them easily and they’re soft in the middle - about 10 minutes. Drain and leave to steam in a colander before tossing in your mint and zest.
For the aioli, take a small bowl and mix together the mayonnaise, garlic, turmeric and lemon juice. Drizzle over the potatoes before serving.
For the bean salad, put all the beans into a pan of boiling water and simmer for 4 minutes. In a small bowl, mix the red onion, red wine vinegar, lemon juice, honey, oil and salt and pepper to taste.
Then take the pink peppercorns and nigella seeds and crush them in a mortar and pestle. Smother the hot beans with the dressing, nigella seeds and peppercorns and serve with the potatoes and lamb.