Melt the dark chocolate in a double boiler, then set it aside to cool.
Line a baking sheet with parchment paper.
Use a food processor to finely chop the pistachios. Reserve 3 tablespoons of these finely chopped pistachios for later. To the remaining pistachios in the food processor, add the melted chocolate, dates, tahini, 2 tablespoons of cocoa powder, and salt. Process until the mixture forms a ball and comes together around the blade.
Remove the mixture from the food processor and knead by hand on a sheet of wax paper. If mixture is crumbly, add 1 tablespoon of coconut oil at a time and knead until you achieve a smooth consistency. If you can easily shape the mixture into any form without adding coconut oil, skip this step.
Roll the dough into ten small balls and place them on the prepared baking sheet. Gently flatten each ball with your hand to create a small disc. Chill until firm, about 20 minutes.
In three separate bowls, place the reserved finely chopped pistachios, sesame seeds, and the remaining cocoa powder. Just before serving, decorate the balls by dipping each into the bowls one at a time, creating an outer coating.
Notes
These balls will keep in the refrigerator for up to 3 days. Enjoy!