With your pairing knife, cut a circle at the top of the pomegranate to remove the lid.
Look inside the pomegranate and gently slice the sides from the top to the bottom. Only slice the outside of the shell where you see the white membrane. Do not slice all the way through.
Place the pomegranate upside down over a large bowl and tap it with a wooden spoon to release the seeds.
Pick out the seeds found in the lid of the pomegranate and throw them in your bowl. Discard everything else.
Place all seeds in a blender and pour the water in. Blend until it forms a juice.
Pour the pomegranate juice into a strainer to separate the liquid from the seed mixture.
Place the spinach in the blender and pour the pomegranate juice on top. Set your blender on chop so that the greens combine with the juice.
Add the bananas and blend until smooth. (NOTE: you can always add more water if it is too thick for your liking)