Peel the carrot, onion and garlic and chop into smaller pieces. Fry the vegetables in the olive oil together with the bay leaves, fennel seeds and thyme for about 3 minutes. Add all the fluids and the halved lemon to your pot. Season with salt and pepper. Split the parsley root and fennel lenghtwise. Simmer in the broth for 20-30 minutes, until soft. Allow to cool in the broth.
Peel the potatoes and boil them gently in salted water until they are soft. Remove the water and pass the potatoes through a sieve. Add the butter with a spatula and add crème fraiche until you have achieved a smooth and creamy texture. Add salt to taste. Smoke with a smoking gun (optional).
Roast the languostine shells in the oven for approximately 5 min at 150°C. Place in a saucepan with the barigoule liquid and diced tomatoes. Bring to the boil and steep for 5 min, strain shells and keep the liquid. Add salt and pepper to taste.
Mix vinegar and double cream, add salt and freshly ground black pepper to taste. Let steep for 5 minutes, then whisk lightly. Cool until serving.
Shell the langoustines according to instruction and place in the fridge to keep them cool. Slice the leek (as many slices as you have guests), steam for 5 mins. Warm the leek with the parsley root and fennel in the oven with some barigoule liquid. Bread the backs of the langoustines with Panko and fry gently in browned butter back down (on the back only). Mix the raw shrimp with the leek ashes. Garnish with sorrel and ripple pine syrup over the top.