This is definitely a restaurant dish but it's easy to make at home. I came up with the idea of curing the trout quickly and then warming it as an alternative to curing it whole and serving it in thin, cold slices. The celeriac is an adaptation of the classic remoulade.
200g table salt
200g caster sugar
1 tbsp coriander seeds, roasted
1 tbsp chopped fresh dill
400g trout fillet, deboned, scaled and cut into 4 fingers
1 small celeriac, peeled and finely sliced into thin strips (see method below)
2 sticks celery, washed and finely sliced on the diagonal
3 tbsp mayonnaise
1 tbsp salted capers, soaked in water for 15 minutes and rinsed
Extra sea salt
Freshly ground white pepper
Combine salt, sugar, coriander and dill in a bowl. Place half on a tray with trout on top. Cover trout completely with remaining mix.
Allow to sit in the fridge for three hours. Remove trout from salt mix and wash.
Dry on paper towel and reserve. Mix remaining ingredients together in a bowl and season. Divide evenly between four plates.
Pan-fry or grill the trout until skin is crispy and the fish is medium rare, about four minutes. Serve with celeriac.
How to julienne vegetables
To slice vegetables into fine matchsticks, it's worth investing in a mandolin - plastic versions are widely available and not too expensive. For the cured trout and celeriac recipe, slice the celeriac thinly on the mandolin. Then take four to five slices, hold firmly and cut into thin strips with a sharp knife, keeping the blade at right angles to your fingers holding the celeriac and being careful not to cut yourself.