Preparation Bring chicken and water to a boil in a 5-quart heavy pot, skimming froth. Add wine, ginger, scallions, and salt and cook at a bare simmer, uncovered, 20 minutes, or until breast meat is just cooked through. Trasfer 1 breast half with tongs to a bowl and continue to cook stock at a bare simmer, skimming froth as neccessary, 2 hours and 40 minutes. Meanwhile, cool chicken breast long enough to remove skin and bones, returning skin and bones to stock. Cool breast meat completely and tear into shreds. Chill shreds, covered, and bring to room temperature before serving. Pour stock through a large seive into a large bowl and discard solids. (you should have about 8 cups: if less, add water; if more, cook longer after adding rice.) Return stock to cleaned pot and add rice. Bring to a boil and stir. Reduce heat to low and simmer, covered until consistency of oatmeal, about 1 3/4 hours, stirring frequently during last 1/2 hour of cooking. (Congee will continue to thicken as it stands. thin with water if necessary.) Season congee with salt. Serve topped with chicken and accompaniments. Cooks' note:• Stock can be made 1 day ahead. Cool. uncovered, before chilling, covered. Discard solidified fat.