Place dates and water in a food processor and process until smooth, stopping to scrape down sides as needed.
Add pureed dates, peanut butter, agave/honey, cacao, and vanilla to small saucepan. Over medium-low heat, stir ingredients for 2-3 minutes, or until combined and softened. Remove from heat.
Add rolled oats and chia seeds to the saucepan. Stir until combined.
Line a baking sheet with parchment paper. Using a cookie scoop, portion out approximately 18 cookies. Use your finger to lightly flatten into a cookie shape.
Place pan in the refrigerator for at least 30 minutes.
Once cookies have cooled and set, remove from pan and store in an airtight container in the refrigerator.
Notes
Cookies keep in an airtight container in refrigerator up to 1 week.