Simply spectacular: Cooking a whole fish not only makes for an impressive presentation, it is also the most foolproof way of making sure the fish stays juicy during cooking (fillets can dry out much more easily, in other words). Here, the gilthead fish is seasoned with salt, pepper, dill, and fresh lemon juice and baked to cook through, and then it's returned to the oven with potatoes and caramelized onions to become an amazingly harmonious meal.