Add water and flax seeds to a high-speed blender. Blend on high for 1 minute.

Strain flax milk through a nut milk bag into a bowl, or through a colander lined with cheesecloth folded over a couple of times. It is helpful to use tongs or your hands to squeeze and coax the flax milk through the bag. (*Tip – If the bag becomes overly clogged and is not straining, simply pour the remaining flax milk back into the blender, rinse nut milk bag off to essentially unclog it, and poor the remaining milk through the bag again.)

Rinse flax seed pieces out of the blender, and add the strained flax milk back into the blender along with the pitted dates, pure vanilla extract, and salt.

Blend on high for 1 minute.

Skim layer of foam off the top of the flax milk.

Cover with a lid, label, and refrigerate.