Coat a medium nonstick skillet with cooking spray; add margarine. Place over medium-high heat until margarine melts. Add onion; saute until tender.
Combine chicken broth, milk, flour, and curry powder, stirring until smooth. Add to onion mixture. Cook over medium heat, stirring constantly, until mixture is thickened. Stir in chicken and next 3 ingredients. Cook over medium heat 6 to 7 minutes or until thoroughly heated, stirring occasionally.
Spoon chicken mixture over rice. Top evenly with banana, chutney, peanuts, and green onions.