Bring the water to the boil in a tall pan along with all the other ingredients up to and including the bay leaf, season with salt, reduce the heat. Add the meat, leave to infuse just below the boil for approx. 1 hr. Remove the pan from the heat, leave the meat to cool in the stock. Set aside 75 ml of the stock. Carve the meat very thinly across the grain.
Puree the trout with the reserved stock, crème fraîche, anchovies, capers and oil, season.
Toast the sunflower seeds in a frying pan without any oil, remove and set aside. Heat the oil in the same pan, fry the apple slices in batches for approx. 1 min. on each side, remove. Arrange the meat and sauce on a platter, top with the sunflower seeds, apple, caper berries and tarragon.