Lamb loin with caramelised onions and rhubarb compote

Begin by preparing the onion purée. Sauté the onions in butter and season with salt and pepper. Deglaze the pan with white wine and keep cooking with the lid on for approximately 30 minutes

Preheat the water bath to 63℃

Meanwhile, make the rhubarb compote. Melt the sugar and glucose together in a heavy-based pan and bring to the boil. Add the butter, rhubarb and apple and simmer for 20 minutes, then season with salt and remove from the heat. Leave to cool, covering with clingfilm until ready to serve

Trim the fat from the lamb loins and cut each loin in half lengthways. Divide the pieces of loin between two vacuum bags and arrange in a single layer, adding pepper, thyme and 200g of the trimmed lamb fat. Seal and cook in the water bath for 15 minutes

To finish the purée, mix the remaining butter through the onions until melted. Transfer to a blender and blitz until smooth, then pass through a sieve into a bowl. Check the seasoning and cover tightly with cling film, reserving until ready to serve

Remove the cooked lamb from the vacuum bags and pat dry with kitchen paper. Heat a frying pan over a high heat and fry the loins until golden on all sides, adding a knob of butter to the pan for basting

Remove the lamb from the pan and leave to rest for approximately 5 minutes. Add the red wine vinegar to the pan and deglaze, then add a few twists of black pepper to taste and set aside

For the baby leeks, bring a pan of salted water to the boil and blanch the leeks for 2–3 minutes, then the chives for 10 seconds. Plunge both into iced water to stop the cooking process, then drain and leave to dry on kitchen paper

Place the baby onions in a medium pan with the water, wine and salt and bring up to the boil. Drain, then add the onions to a frying pan with the sugar and caramelise until golden

Carve the rested lamb loins into rectangular slices, cutting off the crispy meat on the outsides of the loins. Tie the leeks together with the blanched chives to form bouquets

To serve, spoon a little of the onion purée onto each plate and top with slices of loin. Arrange the bouquet of leeks and a spoonful of rhubarb compote to the side of the lamb loin and scatter over the caramelised onions. Drizzle over the deglazed pan juices, garnishing with nasturtium leaves and edible flowers