- 50g/1¾oz caster sugar
- 75g/2½oz salt
- 1 tbsp pink peppercorns
- 1 tbsp coriander seeds
- 2 large bunches fresh dill, leaves chopped
- 1 large salmon fillet, skin and and pin bones removed
- 2 tsp Dijon mustard
- 1 tsp juniper berries
- 10g brown mustard seeds
- 75g/2½oz yellow mustard seeds
- pinch dark soft brown sugar
- 50ml/2fl oz red wine vinegar
- sea salt and freshly ground black pepper
- 75ml/2½fl oz champagne
- pumpernickel bread, to serve (optional)
- Place the sugar and salt into a bowl, then lightly crush the peppercorns and coriander seeds in a pestle and mortar and add them to the bowl. Stir in half of the dill.
- Scatter one-third of the mixture into a large, deep-sided roasting tray. Lay the salmon fillet on top and cover it with the remaining sugar-salt mixture, pressing it gently into the fish.
- Cover the roasting tray with cling film. Place the tray in the fridge for 24 hours to allow the salmon to cure.
- Rinse the cured salmon under cold running water. Pat dry and place onto a chopping board.
- Brush the top of the salmon with the Dijon mustard, then cover with the remaining chopped dill. Set aside.
- Crush the juniper berries in a pestle and mortar, then place them in a frying pan with both types of mustard seeds, the sugar, red wine vinegar and a pinch of salt. Heat the mixture until bubbling, then simmer for 3-4 minutes, or until the seeds have absorbed some of the vinegar.
- Remove the pan from the heat and stir in 50ml/2fl oz of the Champagne.
- Transfer the mustard mixture to a food processor and blend for 3-4 minutes to a fine purée, adding the remaining Champagne halfway through blending. Season, to taste, with salt and black pepper.
- To serve, carve the gravadlax into very thin slices using a sharp knife. Serve with the Champagne mustard alongside and pumpernickel bread, if desired.