Place chia seeds into a medium bowl.
Split the vanilla bean in half lengthwise, scrape out the seeds with the tip of a small knife, and add them to an upright blender.
Place the vanilla pod in a bowl with chia seeds; set aside.
Drain and rinse cashews, and add to blender with 3 cups filtered water, dates, salt, cinnamon, coconut butter, and vanilla extract.
Blend on highest speed until completely smooth, about 1 to 2 minutes.
Pour into bowl with chia seeds along with remaining 1 cup water, and whisk thoroughly. (Alternatively, if you have a large blender with a 6-cup capacity, you can blend in all the water at once).
Let mixture sit for 10 minutes, whisking a couple of times to prevent chia seeds from clumping. Place in the fridge for 1 ½ - 2 hour or until completely chilled.
Remove and compost the vanilla pod before serving.
Divide into bowls, and serve chilled topped with berries. Store and leftover pudding in a jar in the fridge for up to five days.