CHOCOLATE-COVERED SHORTBREAD

Steps:

• Preheat the oven to 300˚. Lightly butter the bottom and side of a 9-inch fluted tart pan. Combine the all-purpose and whole-wheat flours, confectioners' sugar and salt in a food processor and pulse until combined. Add the butter and vanilla and pulse until the flour is moistened and the dough just begins to clump together.
• Press the dough evenly into the prepared pan. Prick the dough all over with a fork, about 30 times.
• Bake until the shortbread is lightly browned and set in the center, 1 hour to 1 hour 10 minutes. Transfer to a rack and let cool 10 minutes in the pan, then sprinkle with the chopped chocolate. Let the chocolate soften, about 5 minutes, then spread into a thin layer with an offset spatula, leaving a 1/2-inch border around the edge. Top with nonpareils; let cool completely.
• Remove the tart from the pan and transfer to a cutting board. Cut into thin wedges.