Place the ingredients for the smoothie base in a high powered blender. Blend until smooth starting on a low speed and working up to speeds 7-8 on a Vitamix. If you don't have a high powered blender, use 1 Tablespoon of vanilla extract instead of the vanilla bean.Pour the smoothie base into 4 bowls, and top with granola, sliced banana, and your choice of seeds.Serve immediately.