Slice one quarter off stem end of each pepper; reserve tops. Remove membranes, seeds and stems. Invert peppers on waxed paper. Chop tops (you will need 1/2 cup; save rest for other use).
Sauté chicken, chopped peppers, salt, ginger and black pepper in oil in saucepan 8 minutes, until no longer pink. Sprinkle in rice; add sauce and boiling water; stir. Return to boiling; cover; remove from heat; let stand 5 minutes. Stir in water chestnuts. Turn into bowl.
Wipe out pan. Add 1/2 cup water. Place steamer basket in pan.
Divide chicken mixture among peppers. Place upright in basket. Cover; steam 10 to 15 minutes, until tender. Makes 4 servings.