Line an 11x7-inch baking dish with parchment paper.
Add nuts to a food processor. Blend until they resemble a crumb consistency.
Add egg white and cocoa powder and process for 30 seconds, scraping sides if needed.
Quarter dates and add to mixture. Process 1-2 minutes or until you have reached a sticky consistency.
Refrigerate for 1 hour.
Pull out of baking dish by lifting parchment. Cut into 20 bars. Add to an airtight container, placing parchment between layers to avoid sticking together.