Preheat oven to 350 degrees. Grind a half cup of pistachios in the food processor until very fine, and set aside. Grind the other half cup until coarse and set aside.
Beat vegan butter and sugar with an electric mixer until fluffy. Add the applesauce, mix until combined.
Combine gluten free flour, finely ground pistachios, and salt and add to the wet ingredients a little at a time until incorporated.
Divide dough into 2 equal parts; flatten each portion into a disk. Wrap in plastic wrap and refrigerate for about an hour.
Place 1 portion of dough on a lightly floured surface, and roll to ¼-inch thickness. Make sure your rolling pin is coated with GF flour. If you haven’t tried to roll GF dough before, it can be sticky! Flouring the surface and the pin thoroughly help make it easier.
Cut out round shapes with a two inch fluted biscuit cutter. Carefully lift the rounds up with a thin spatula and transfer to a parchment lined cookie sheet.
Bake at 350 degrees for 10 minutes for 2 inch cookies. (Keep an eye on them, the edges should be lightly golden brown. Don’t let them burn! Let them cool for a few minutes on the cookie sheet, then transfer to wire racks to cool completely.
Melt the chocolate chips in a glass bowl in the microwave. I start with one minute, stir, and then do 15 second increments until they are melted and smooth.
Spread the melted chocolate over half of each cookie, and then dip in the coarsely ground pistachios. Set on waxed paper to cool and let the chocolate firm up.