Add cashews, 4 cups filtered water, vanilla extract or sweetener of choice, and salt to a high-speed blender.
Blend on high for 2 minutes - set a timer.
Transfer to a pitcher and refrigerate until well chilled.
Stir or shake well before serving.
Notes
If not using a high-power blender, strain cashew milk through a nut milk bag after blending.For Whole30 omit sweetener and vanilla extract.For keto use stevia or low carb sweetener.