Ideally, you would want two 500 gram (1 lb) skin on fillets from the center cut of the fillet, remove the pin bones if that is not already done. But you can use the smaller fillets from Tesco, as what is in this photo. When I make this, I will use two of these fillets on the bottom, and two on top, just reduce the salt and sugar in equal proportions.

Mix together the salt, sugar, and white pepper. Rub the mixture into both sides of the salmon fillets.

Put half of the dill between the fillets, then divide up the remaining dill between the top and bottom, place in a ziplock bag and seal after removing as much as as you can. Place the bag in a backing dish and place a smaller dish on top and weight it down with some canned goods.

Place in the fridge for 24 to 48 hours, flip the bag about every 12 hours.

Remove from the fridge and remove from the dish. Rinse the fillet very well with cold water, and use your fingers to rub off all the salt and dill. Dry the fillets with paper towels.

Place a fillet skin side down on your cutting board, hold your knife at a angle and slice as thin as you can down to the skin but not through the skin. Repeat with remaining fillet or fillets.

Mix together the mustards and sugar, stir until the sugar is dissolved. Stir in the vinegar.

Using a mixer or food processor, very slowly add the oil, continuously mixing, start with just drops at first and when it binds (like making mayo), you can increase the amount of oil you are adding at a time. Season with salt and white pepper to taste. Mix in the dill.

Serve with the sliced salmon as an appetizer on rye bread or with boiled potatoes for a lunch or dinner.