In a small bowl combine the prepared prunes, date, cranberries, almonds, and cinnamon. Stir to coat the fruit completely. Set aside. 

Place butter and sugar in the bowl of a stand mixer. Chill until the butter is firm, about 30 minutes. 

Whisk together the flour and salt; add to the bowl with the butter and sugar.  

Using the paddle attachment, mix on low speed until dough starts to resemble a coarse meal, about 5 minutes. Increase speed to medium and mix 2 to 3 minutes more, until the dough starts to clump together in the bowl or around the paddle.  

Add the cinnamon coated fruit mixture and the pearl sugar pieces to the bowl with the dough and mix on low just until everything comes together. 

On a lightly floured work surface, roll the dough into a cylinder, then pat it into a rectangle. Lay a large sheet of parchment paper on the work surface and dust it lightly with flour. Put the dough on top. Start rolling the dough, stopping to push together any cracks that form. To keep the dough from sticking, dust the top lightly with flour and cover with another piece of parchment paper.  

Continue to roll the dough until it reaches a ¼-inch thickness, approximately a 10x13-inch rectangle in shape. Transfer the dough and parchment to a baking sheet. Cover with another piece of parchment and chill until firm, at least 20 minutes, preferably several hours or overnight. 

Preheat oven to 350°. Let the dough sit at room temperature for up to 10 minutes.  

Invert the dough onto a work surface and peel off the top sheet of parchment paper. Using a knife, pastry wheel or cookie cutters, cut dough into desired shapes. Use up remaining scraps of dough by combining and re-rolling.  

Arrange 12 to 16 cookies on baking sheets lined with parchment paper. Pierce each cookie with a fork multiple times. Transfer the pans to the oven, lower the temperature to 325° and bake for 10 minutes.  

Rotate pans and bake until cookies feel firm to the touch and are lightly golden brown, 6 to 8 minutes more. Let the cookies cool completely on the pan. 

Enjoy immediately or store in an airtight container for up to 1 week. 

To decorate the cookies:  

In a small bowl whisk the powdered sugar and milk together until completely smooth. Dip a small portion of each shortbread cookie into the icing. Allow excess to pour off. Place the cookie back on the sheet pan. Sprinkle the prepared pistachios and cranberries over the wet icing. Leave undisturbed, the icing will set within a few hours.