Finely chop and sauté the leek.
Once soft, add the chopped prawns, the pecans (broken up by hand) and the raisins.
Add the pine nuts to a frying pan with a little oil and fry until they are browned.
Wash, stem and salt the mushrooms then add them to a frying pan with some oil.
Once they have browned on one side, turn them over and fry the other side.
Stuff them with the filling and serve on a bed of green leaves with the toasted pine nuts.