Pull skin from chicken breasts, cut meat from bones; cut into thin strips.
Marinate chicken with teriyaki sauce or soy sauce in a bowl for 15 minutes.
Heat oil in a large skillet; remove chicken from sauce; brown quickly in hot oil.
Add yellow squash and green beans.
Saute, stirring gently, 3 minutes, or just until shiny moist.
Add remaining teriyaki sauce or soy sauce, water, lemon juice; cover; steam 5 minutes.
While vegetables steam, drain liquid from pineapple into small cup; stir in cornstarch to make a smooth paste.
Add pineapple tidbits and sliced water chestnuts to skillet; heat just to boiling.
Stir in cornstarch mixture; cook, stirring constantly, until mixture thickens and bubbles 3 minutes.
Stir in your favorite low calorie sweetener, using the equivalent of 1 tablespoon sugar.
Serve with Chinese noodles, if you wish (70 calories per 1/3 cup).