Crunchy salad with langoustines

Salad
- 500g of langoustines 10/15 cm
- 1 fennel
- 1 carrot
- 1 cucumber
- 1 yellow courgette
- 1 green courgette
- 1 bunch of radishes
- 1 beetroot
- 150g of mixed salad

Langoustine juice
- langoustine shells
- aromatic garnish
- 1 onion
- 2 tomatoes
- 3 cloves of garlic
- 1 bouquet garni
- branch of fennel
- 50 g butter
- peanut oil
- 1 glass of dry white wine
- ½ glass of Cognac
- Salt, pepper

Vinaigrette with traditional mustard
- 1 tablespoonful of Fallot traditional mustard
- 3 tablespoonfuls of walnut oil
- 1 teaspoonfuls of balsamic vinegar
- 2 teaspoonfuls of sherry vinegar
- Yellow mustard seeds
- Salt, pepper

Shell the langoustines and put the tails to one side.
Brown theheads, claws and shells well in a casserole dish and add the aromatic garnish; sweat the mixture. Deglaze with the Cognac and the white wine, reduce and then add water to cover. Bring to the boil and cook for 20 minutes. Strain and filter the mixture and reduce to glaze (equivalent of a glassful). Add the traditional mustard and the vinegars, emulsify the mixture with the walnut oil, and season to taste.
Wash the vegetables and peel the fennel, the carrot, the cucumber and the beetroot. Wash and sort the mixed salad. Slice the vegetables thinly with a mandolin, plunge them into chilled water for 5 minutes, drain them and mix them with the salad.
Sauté the langoustine tails in a very hot pan and then roll them in the mustard seed mixture.
Season the salad and arrange all the food harmoniously.