Slice Chicken into strips. Dissolve bouillon cube in boiling water. Heat oil in skillet or wok. Over medium heat Add chicken,cooking and stirring constantly until chicken is done and slightly browned. remove chicken to side.
Add mushrooms, onion, celery, water chestnuts, salt, ginger, mgs, and mixed vegetables. Cover and reduce heat to low. Cook 10 minutes
Mix cornstarch with soy sauce and sir into pan with chicken and vegetables. Cook for 5 more minutes.