Put the barley in a medium saucepan and cover generously with water. Bring to a boil, turn the heat to medium and simmer for 25 - 40 minutes, testing regularly, until the grains are cooked but still retain a bite. Drain, refresh under cold water, and set aside to dry.

Heat the oven to 180°C. Put the salmon skin side down in a 26cm x 18cm baking dish. Add the wine, bay leaves, thyme, allspice and peppercorns, and sprinkle the fish with 1⁄4 teaspoon of salt. Cover the dish with baking paper and foil, and bake on the middle shelf for 14 - 18 minutes, depending on thickness, until the fish is just cooked but still pink in the middle. Remove from the oven and carefully strain the cooking liquids into a small pan; discard the aromatics. Cover the fish with foil and set it to one side.

Heat the pan containing the cooking juices over a medium heat and reduce for about 10 minutes, until you have two tablespoons of thick liquor left. Allow to cool slightly, then whisk in the lemon juice, two tablespoons of the oil, 1⁄4 teaspoon of salt and a generous grind of pepper. Set aside until ready to serve.

Bring a large pot of water to a boil. Add the beans (or asparagus, if in season) and cook for about four minutes, until bright green and tender-crisp. (If using asparagus, it will require less cooking time than the beans). Drain, refresh under cold water and set aside to dry (speeding up the process by spreading the beans out on a clean tea towel).

Put the beans in a large bowl and mix in the barley, spring onion, tarragon, most of the chervil (or parsley), the remaining tablespoon of oil and a generous pinch of salt, and divide between six plates. Break the salmon into chunks, removing any skin, and arrange over each portion. Dot small spoonfuls of cream cheese on top and drizzle over the dressing. Sprinkle over the nigella seeds and remaining chervil, and serve.

Recipe by Yotam Ottolenghi featured in The Guardian | Photograph: Johanna Parkin for The Guardian