Method: (Preheat oven to 180°c, light barbecue)
Fillet the turbot and portion into 150g pieces and reserve on a cloth.
Make the celeriac by mixing the rock salt, ash, flour and egg whites together to make a dough. Place the celeriac onto an open flame until black on the outside before removing and allowing to cool. Roll the dough out to 1cm thick and wrap around the celeriac. Place into the preheated oven for 1 hour. Once the celeriac is baked remove from the oven and allow to cool for 30 minutes before cutting the celeriac from the crust. Slice the skin from the celeriac and reserve to one side for the sauce. Slice the flesh of the celeriac into 2cm thick slices and cut with a 4cm ring cutter. Reserve to one side for garnish.
To make the sauce take a medium saucepan and gently heat the oil, slice the shallot and garlic and add these to the pan and cook until soft and translucent. Next, add the white wine and cook on a high heat until reduced to a glaze before adding the chicken stock and water, now add the celeriac trimmings and bring to the simmer. Cook gently until the mixture has reduced by ¾ (500ml). Season lightly with salt and thicken with the kuzu.
Place the sauce to one side and allow to cool slightly.
Take the fennel bulbs and cut into quarters and season heavily with salt. Heat the olive oil in a wide base pan and add the fennel, cook on all sides until well coloured before adding the thyme and garlic. Next, add the white wine and reduce to a glaze, followed by adding the chicken stock. Bring this to a simmer before covering with a cartouche and placing into the oven for 20 minutes. After 20 minutes the sauce should be well reduced and the fennel tender.
For the mushroom puree, melt the butter in a medium sized saucepan until foaming, finely slice the onion and add this to the pan and sweat gently until translucent before slicing the mushrooms and adding these to the pan as well. Lightly season and cook until all the moisture has evaporated before adding the cream. Cover with a cartouche and place into the oven for 20 minutes. Once cooked, remove from the oven and place into a food processor and blend well until smooth.
To make the mushrooms place a large pan on a heat and add the butter and finely chopped shallot and garlic. Cook gently until soft before chopping the mushrooms roughly and adding to the pan, season the mushrooms well and continue to cook until the mushrooms are tender and well coloured before adding the chicken jus to glaze and finish with the cream. Remove from the pan to cool slightly before chopping roughly.
Blend the dried cep mushrooms in a spice grinder until it becomes a fine powder. Slice the button mushrooms on a mandolin and dust with the cep powder.
To cook the fish brush the skin side with a little oil and place onto the barbecue making sure no flames scorch the fish, cook for 8-10 minutes, moving occasionally and making sure the fish does not stick. Once cooked season with a drop of fresh lemon juice.
To plate the dish place a pool of the mushroom puree onto the plate and place the fish on top, Place the fennel onto the plate and garnish with the fennel tops, next to the fish with the duxelle, baked celeriac and sliced raw mushrooms. Whisk the sauce and pass through a fine sieve before pouring around the fish.