Recipe from Ricki's Kitchen:

"Mystery" Smoothie  

Use this smoothie as a full breakfast. When you include blueberries, the kids won’t know that the drink is also brimming with healthy minerals and extra protein from the greens that have “mysteriously” made their way into it! The carob powder contributes extra calcium, and the nutritional yeast extra B-vitamins and proteins, to this nutrient-dense drink. 

1-1/2 to 2 cups soy milk, rice milk, or juice
1/2 cup blueberries or mixed berries, fresh or frozen
1/2 banana, fresh or frozen
1/2 cup chopped mango, peaches or apricots, fresh or frozen
1-2 tsp. agave nectar or maple syrup
1 tsp. carob powder (optional)
1 tsp. nutritional yeast (optional)
1 tsp. pure vanilla extract
1/2-1 cup packed fresh spinach or swiss chard leaves, washed and well-drained

Blend all ingredients together in a blender until smooth and no specks of the greens remain.  Pour into glasses immediately and enjoy! Makes 4-6 servings.