Cut the chicken into 1/2-inch cubes. Combine 3
tablespoons sherry and 1 tablespoon soy sauce in
medium bowl. Add chicken and marinate for 1 hour or
overnight. Pour enough water into wok to come just
below steaming rack. Bring to a boil. Place chicken
on one side of shallow baking dish. Arrange mushrooms
alongside chicken and water chestnuts alongside
mushrooms. Set dish on rack in wok; cover and steam
until chicken and vegetables are tender, about 20
minutes. Place snow peas over vegetables in dish;
steam until peas turn bright green, 2 to 3 minutes.
Meanwhile, combine remaining sherry and soy sauce with
the water, oyster sauce, cornstarch, and sesame oil in
medium saucepan over medium heat. Cook and stir until
thickened, about 5 minutes. Serve chicken and
vegetables over rice. Pass sauce separately.
