Sturgeon with caviar, fennel and dill oil

Begin by making the aromatic rapeseed oil. Place all the ingredients in a pan and warm to 90°C. Turn the heat down so the oil stays at around 70°C, then leave to infuse at this temperature for 3 hours. Pass through a fine sieve into a jug. You will need 140g of the oil for this recipe, but the rest (around 60g) can be used to cook or dress a variety of other dishes

Make the dill oil by blitzing all the ingredients in a blender for 8 minutes, or until hot. Strain through muslin cloth set over a bowl and place in the fridge to collect the bright green oil

For the fennel sauce, heat 10g of the butter and the olive oil in a large saucepan. Add the shallots, fennel, mushrooms, fennel seeds, salt and lime juice and cook over a low heat until soft (do not allow to colour)

Add the fish stock, white wine and vermouth, bring to a simmer and reduce by half. Add the whipping cream, bring to a rapid boil and cook for 1 minute, then strain through a fine sieve into a blender (push down on the solids to extract as much liquid as possible)

Blitz the mixture adding the remaining 30g of butter, the fennel fronds and spinach, until smooth and bright green. Add the Pernod and xanthan gum, blend for 20 seconds to combine, then pass through a sieve into a pan. Cover and store in the fridge to reheat later

Prepare the shaved fennel by quartering the head and cutting very thin slices of it using a mandoline. Keep the slices in iced water as you work to keep them crisp and fresh

Place the lime juice, salt, finger lime seeds, fennel fronds, fennel pollen and 10g of the aromatic rapeseed oil in a bowl and mix to combine. Transfer the fennel slices into the bowl and set aside to marinate

To cook the sturgeon, mix the salt, sugar and fennel seeds together and rub all over the loin. Set aside to cure for 15 minutes, then wash and pat dry

Use a blowtorch to sear the fatty side of the sturgeon until golden brown, then cut into 4 equal portions and set aside to cook before serving

If you have a sous vide, cook the fennel flames by preheating a water bath to 95°C and preheating an oven to 180°C/gas mark 4. Cut the fennel into 4–6 wedges and shape them into flame-like shapes with a knife. Season with the salt and place in a vacuum bag with 80g of the aromatic rapeseed oil. Seal and cook for 18–20 minutes until soft, then drain

If you don’t have a sous vide, cut the fennel into flame-like shapes as above but pan-fry in the aromatic oil until golden brown all over and season

Once the fennel flames have been cooked either sous vide or in the pan, transfer to a baking tray and cook in the oven for 8 minutes until soft

Meanwhile, cook the sturgeon. If you have a sous vide machine, place the sturgeon into a vacuum bag with 50g of the aromatic rapeseed oil and seal, then cook at 55°C for 15 minutes. Alternatively heat 50g of the aromatic oil in a pan and fry the sturgeon until golden brown on both sides. Transfer to the oven and cook for a further 3 minutes, then allow to rest for 2 minutes

Gently reheat the fennel sauce and pour 30ml of the dill oil into the base of a jug (any leftover can be kept in the fridge for other dishes)

Dress the sturgeon fillets with a little lime juice and divide between 4 bowls. Place the fennel flames alongside and arrange the sliced marinated fennel on top. Garnish with caviar and wild fennel tops, then pour the hot fennel sauce into the jug with the dill oil (this will cause it to split). Serve and pour the sauce into the bowls at the table