Process all ingredients in a blender 1 to 2 minutes or until smooth, stopping once to scrape down sides. Serve immediately.
Peanut Butter-Banana Shake: Add 2 to 3 tablespoons creamy peanut butter before processing.
Strawberry Shake or Strawberry-Banana Shake: Substitute 2 cups frozen sliced strawberries for bananas, or combine 1 cup frozen sliced strawberries and 1 banana, sliced and frozen.
Pineapple-Orange-Banana Shake: Substitute 1 cup pineapple-orange juice for milk.
Note: Leftover shake mixture may be frozen in small cups or ice-cream cones and served as a frozen snack.