Add medjool dates and water to the pitcher of a high-speed blender. If necessary, let sit for 10-30 minutes, until softened.
Add the almond butter, vanilla, pinch salt, and cinnamon if using. Puree on high speed until completely smooth, a minute or two. Add more water, a tablespoon at a time, if needed to keep things moving.
Transfer to serving bowl. Keeps in an airtight container in the refrigerator for several days ... um, it never really lasts that long around here.