Perch, tench, soles, eels, and flounders are considered the best fish for this dish. For the souchy, put some water into a stewpan with a bunch of chopped parsley, some roots, and sufficient salt to make it brackish. Let these simmer for 1 hour, and then stew the fish in this water. When they are done, take them out to drain, have ready some finely-chopped parsley, and a few roots cut into slices of about one inch thick and an inch in length. Put the fish in a tureen or deep dish, strain the liquor over them, and add the minced parsley and roots. Serve with brown bread and butter.