I know what you are thinking - YUCK! Trust me, this smoothie tastes nothing like spinach. It will turn out very green though, so if that is off putting you shouldn't drink it in a clear glass.
1 ripe banana
1/2 cup frozen mango
1/4-1/2 cup apple juice
1/4 cup plain, nonfat yogurt
1 cup packed, fresh spinach, washed thoroughly
Place mango and spinach in the blender jar first. Top with juice, yogurt and banana. Blend like hell and when you think it is smooth enough, blend it some more. Enjoy immediately.