Place everything EXCEPT the chia seeds in a high speed blender and blend on high until everything is smooth.
Pour the mixture into a jar or sealable container, then add the chia seeds. Mix the seeds all around, then allow it to sit for 5-10 minutes. Stir everything again to make sure the chia seeds don’t all settle to the bottom.
Cover and place in the fridge for 3+ hours, or overnight.
Top with additional banana pieces and sunflower butter before serving (optional).