2 tsp. granulated sugar, for sprinkling on top of pre-baked shortbread
Preheat oven to 350 degrees F. Place a rack in the middle of the oven. Lightly spray a 9-inch tart pan with a removable bottom with Baker’s Joy® No Stick Spray with Flour.
In a medium bowl, whisk together flour, espresso powder, Clabber Girl® Baking Powder and salt. Set aside. In the bowl of a stand mixer fitted with a paddle attachment, cream together the Crisco® All-Vegetable Shortening, unsalted butter and confectioners’ sugar on medium speed until light and fluffy. Add the vanilla extract until well combined. Turn the mixer to low and slowly add the flour mixture, just until the dough starts to form large clumps. Stir in the chopped chocolate chunks with a wooden spoon.
Spread the dough evenly into the prepared pan, smoothing the top with your fingers or a rubber spatula. Using a fork, prick the entire surface of the dough about 1/4 inch deep, and about every 1/12 inches. Sprinkle the 2 tsp. granulated sugar over the top of the dough. Place the pan on a baking sheet and bake until lightly browned, about 25-30 minutes.
Remove from the oven and slice into 8 wedges while the shortbread is still warm. Cool in the pan, then remove from tart pan. Shortbread can be stored in an airtight container at room temperature for up to 5 days.