Soak the almonds at least overnight, up to 24 hours, in 2 cups of the water. Drain, then place in a blender with 1 1/2 cups of water. Add vanilla, and dates, maple syrup, or cinnamon, if using. Blend on high for 3 minutes, scraping down the sides of the blender as needed. If you like a thinner consistency, add up to 2 more cups of the water and blend for 1-2 more minutes. Allow to rest for 1 hour in the blender. Taste, and add more maple syrup, another date, or one more sprinkle of cinnamon if needed. Blend well, at least another minute.

Place a fine-mesh strainer over a large bowl. Cover with a nut milk bag or several layers of cheesecloth. Pour the almond milk through the strainer. After letting it drain for a few minutes, gently press the pulp with the back of a spoon to extract more milk. After about 20 minutes of draining, draw up the edges of the nut bag or cheesecloth, and squeeze it into a ball, pressing it with your hands to extract the last drops of almond milk. Pour milk into a jar, tightly cover, and keep refrigerated for up to 4 days. Give the jar a shake before enjoying.