For the marinated salmon: Remove any remaining bones from the salmon, using a pair of fish tweezers. Using a sharp knife, slice through the skin in three lines down the centre of the fish, being careful not to go too deep into the flesh. Mix the chopped dill and lemon zest with the salt, sugar and pepper. Sprinkle half this mixture onto a tray, and lay the salmon, skin side down, on top. Now sprinkle the remaining mixture onto the flesh side of the salmon and rub in. Cover with clingfilm and leave to marinate for 12 hours. For the Gravlu: Wash the marinade off your marinated salmon and pat dry. Place on a board, skin side down, and brush the flesh side with the Dijon mustard. Sprinkle over the chopped dill and pat down. Wrap in clingfilm and put into the fridge for 3 hours. Potato pancakes: To make the potato purée, bake a jacket potato in the oven on a bed of salt until soft. Cut in half, scrape out the potato flesh and pass through a ricer or sieve. Sift the flour into a bowl. Add the egg and egg yolk and mix to a batter, then gradually add the milk, whisking until smooth. Add the potato purée, yoghurt and a teaspoon of oil, season with salt and pepper and mix well. Heat a little oil in a non-stick pan. Take tablespoons of the mixture and drop them in the pan, leaving enough space between them to be able to turn them. (You will need to do this in batches.) When golden brown, flip them on to the other side and cook until golden brown on that side too. Remove to a tray and set aside and keep warm. To serve: Put the soured cream into a bowl and add some chopped chives. Take the salmon out of the fridge, place it on a wooden board and slice thinly, using a sharp salmon knife. Take a warm pancake and top with a sliver of salmon, a squeeze of lemon, a dollop of soured cream and a sprinkling of chives. Planning ahead The salmon needs 12 hours to cure, and the gravlax requires a further 3 hours after that, so my advice is to cure the salmon overnight and then make it into gravlax the following morning. Once made, the gravlax will keep for at least 5 days in the fridge.