Season 6 trout with salt and a little pepper, dip them in milk, then in flour, and saute in hot oil about 1/4 inch deep in the pan until golden brown on both sides. Drain the oil from the pan. Put a piece of sweet butter in the pan, 1 tablespoon for each serving, and cook until it turns a nut-brown colour. Pour this over the fish and sprinkle the top with chopped parsley and lemon juice.