Smoked haddock with leek and grain mustard sauce

Method

Slice leeks into 1cm rounds, wash thoroughly and set aside. Heat 25g butter in a heavy-bottomed pan over medium heat, sweat the minced shallot until translucent, then add white wine and reduce by half. Pour in stock and bring to a simmer. Add leeks with thyme sprigs and poach gently for 8-10 minutes until tender but holding their shape; remove leeks with a slotted spoon and keep warm. Whisk grain mustard and cream together, then slowly add to the simmering stock whilst whisking to avoid splitting; season carefully with salt and white pepper. Pat haddock fillets dry and season skin-side lightly with sea salt. Heat remaining butter in a non-stick pan until foaming, place haddock skin-side down and cook for 4-5 minutes until skin is crisp and flesh is just opaque; turn briefly to finish. To plate, spoon warm leeks into the centre of bowls, place haddock fillet on top, ladle sauce around and finish with a squeeze of lemon juice and fleur de sel.