Roasted langoustines, oyster purée, celery, and horseradish

Begin with the celery slices. Peel and wash the celery making sure all the strings are removed. Cut into thin slices. Place in a vacuum bag, add the celery essence and seal in a chamber sealer to compress. Set aside in the bag until ready to serve

To make the celery gel, use a juicer to extract the juice from the celery then weigh out 125g into a clean bowl (discard any extra). Sprinkle in the ultratex and whisk together until fully incorporated. Season with a little salt and transfer to a piping bag. Chill until ready to serve

For the horseradish foam, bring the cream and milk up to the boil in a small pan then remove from the heat. Mix in the grated horseradish and allow to cool

Strain the cream through a sieve and season to taste. Transfer the mixture to a 500ml siphon gun, turn upside down and charge once. Reserve until ready to serve

For the oyster purée, rinse the oysters then place in a blender with the parsley and whizz together. Add the oil slowly to emulsify as for a mayonnaise. If too thick add a little of the reserved oyster juice

Taste the resulting purée and season with a squeeze of lemon juice. Transfer the mixture to a piping bag and reserve in the fridge until ready to serve

Take the whole oysters and open the shells. Drain off any juice and rinse the oysters. Slice the meat thinly and reserve in the fridge until ready to serve

To cook the langoustines, bring a pan of water to the boil over a medium heat. Blanch the langoustines for just 5 seconds then refresh immediately in a bowl of of iced water. Drain and remove the shells by pinching them from top to bottom then peel the shell away from the flesh

Place a frying pan over a medium heat, add the oil and quickly fry the langoustines until cooked through but without allowing them to brown. Season with a little salt to taste

To serve, dot the oyster purée and celery purée over each serving plate. Add the slices of oyster and the fried langoustines, followed by the compressed celery slices (removed from the vacuum bag)

Siphon the horseradish foam in dots over the plates then garnish with the celery leaves