The softly cooked lasagne sheets are cooled down and dabbed dry, then the fish, cut into cubes and seasoned with salt, pepper and the juice of a lemon, is spread on top, together with a beaten egg. Roll up as tightly as possible and cook the cannelloni in a gratin dish covered with butter flakes and aluminum foil in a heated oven at 180 degrees for about 8 minutes.
Cut leek into rings, sauté in butter, season with salt and pepper and extinguish with white wine and cream. Simmer for about 4 minutes. Finally add chopped chervil.
Serve the cannelloni with the leek ragout and garnish with the remaining chervil.