Recipe and photo from FULL BELLY © 2014 Tara Mataraza Desmond, Running Press, a member of the Perseus Books Group.
Dump the cashews, almonds, and salt into a food processor and pulse about fifteen times to pulverize to a bitty meal. Sprinkle the cocoa across the mixture and then pulse another fifteen times to work it into the meal.
Add the cherries, raisins, and dates and process in intervals of 20 to 30 seconds four times, stopping to scrape down the sides. Blending the ingredients will be noisy at first, but the sound will dull to a hum as the ingredients are ground together into a finer meal. When the mixture is ready, it will still appear crumbly, but it should stick together if you squeeze a bit of it in your fist. The nut oils and natural stickiness of the fruit will bind everything as it is rolled and chilled.
Scrape the mixture out onto a large piece (about 24 inches/61 cm) of waxed or parchment paper and squeeze it together into a pile situated on one half of the paper. Fold the other half of the paper over the pile and push it down with the palm of your hand into a relatively even thickness in a shape that resembles a rectangle. Then use a rolling pin to roll the paste into an 8 x 6-inch/20 x 15 cm rectangle about ¹/2 inch/1.3 cm thick. Don't worry too much about the exactness of the rectangle and the precision of the edges, just work it into a shape from which you can easily cut relatively evenly sized bars. Transfer to the freezer for 15 to 30 minutes, or until cold and firm but not frozen. Peel off the paper and cut into twelve equal-size bars about 4 inches/10 cm long and 1 inch/2.5 cm wide.
Refrigerate in an airtight container with waxed paper or parchment paper between each layer of bars for up to 5 days.