A delicious winter/spring dish, with a serious feel good factor. The fish in its reduction/dressing is divine, sweet and warm and a little bit herby, while the lentils and greens go very well indeed with them

1 tbsp olive oil

1 leek, finely sliced

350ml fish stock or vegetable stock

Zest of 1 lemon, and the juice of half of it

1 tbsp fresh tarragon, finely chopped

1 x 200g boneless haddock fillet, skin on

200g spring greens, destalked and finely shredded

1 x 250g pack cooked beluga or puy lentils

½ - 1 tbsp soy sauce

1 tbsp full fat crème fraiche

4 x very finely diced cornichons

• Heat the oil in a medium saucepan, and cook the leeks with a pinch of salt for 8 minutes over a low heat, stirring occasionally, until lightly golden

• Meanwhile in a larger pan, bring the stock, half of the lemon zest and half of the tarragon to the boil. Ease in the haddock fillet so that it is flat, reduce the heat until just bubbling and cook for 6-8 minutes, until the fish is just poached. Gently lift out, keeping in on piece, lift it off its skin and keep warm

• Remove 2 tablespoons of poaching liquid. Add half the greens to the leeks along with 1 tablespoon of the reserved liquid. Cook for a minute then add the remaining greens and liquid. Once wilted, stir in the lentils, and keep warm

• Meanwhile, to make the sauce turn the heat up under the remaining stock and add the rest of the zest. Bring to the boil and reduce by half, then turn the heat down, season with pepper and soy sauce, add the remaining tarragon and crème fraiche. Finally, add the cornichons

• Divide the veg/lentils between two plates. Divide the fish and place on top. Drizzle over the sauce and serve with lemon wedges