Preheat oven to 375 F (175 C). Grease inside of roasting bag and put it on a heatproof cookie sheet.
Using a food processor, blend butter, lemon juice, parsley, shallot and black pepper for about 3 minutes using the pulse button. Do not over do. The butter should be speckled with the herbs.
Spoon the butter onto a plate and allow to set. Cut butter into 1/4 inch chunks. Set aside.
Wash barracuda with water. Place fish inside the roasting bag and top with the breadfruit and chunks of butter. Carefully roll up the bag opening in the direction of the top of the bag to keep in the heat, prevent the juices from leaking and to ensure a good blending of flavors.
Bake in the oven for 45 minutes, or, if using a barbecue, follow the barbecue's manual directions for foil baking fish according to weight. Serve hot garnished with parsley sprigs, accompanied by a salad.