Whole grey mullet need the guts, scales and gills removed. Fillets also require pin-boning but (once scaled) the soft skin is usually left intact. Grey mullet has a distinctive, almost earthy flavour that is not universally loved. This earthiness can be reduced by the addition of robust and lightly acidulated sauces, dressings and marinades featuring lemon, white wine vinegar, capers and garlic.http://www.helpwithcooking.com/fish-guide/baked-grey-mullet.html
Just find a way to not use aluminum foil
Boggy Bayou Mullet Festival in Florida offers a tasty chowder recipe: Fry ½ lb. of chopped salt pork in a Dutch oven until lightly browned. Add two chopped onions, 1 cup of diced celery, three minced garlic cloves and one chopped green pepper. After cooking for five or 10 minutes add one large can of tomatoes, one can of tomato paste, 2 tbsp. of Worcestershire sauce, 1 tsp. of hot sauce, 1 tbsp of salt and 2 tsp. of black pepper. Cook 10 more minutes and add 1 pint of boiling water, eight potatoes cut into chunks and two large carrots, sliced. When the potatoes are nearly done, add 3 ½ lb. of mullet fillets and simmer until the fish are flaky. This recipe serves six to eight people.