Make the white layer. In a smoothie cup or blender cup, add the Greek yogurt, banana slices, and coconut water. Blend until smooth. Place the smoothie in a cup and place it in your refrigerator to chill while you make the other layers.
Make the blue layer. In a smoothie cup or blender cup, add the Greek yogurt, banana slices, coconut water, and blue spirulina powder. Blend until smooth. Place the smoothie in a cup and place it in your refrigerator to stay chilled while you make the other layers
Make the pink layer. In a smoothie cup or blender cup, add the Greek yogurt, strawberries, and coconut water. Blend until smooth. Transfer to another cup and refrigerate while you make the other layer.
Make the purple layer. In a smoothie cup or blender cup, add the Greek yogurt, strawberries, coconut water, and blue spirulina powder. Blend until smooth.
Assemble. Remove all 4 color cups from the fridge and, using a spoon, layer the colors in a 16oz glass. Use a skewer or pointed knife to poke around the side of the glass, swirling the colors just slightly. (Optional: You can also drink it striped.)
Garnish and enjoy. Top with whipped topping, sprinkles, and a straw. Enjoy immediately.