'OREO' COOKIES

Steps:

• Prepare the dough: Sift together the cocoa powder, flour and salt in a large bowl.
• Using a mixer, cream the butter and sugar. Add the eggs one at a time, then the vanilla, incorporating each ingredient before adding the next. Add the dry ingredients and mix just until incorporated, scraping the bottom of the bowl with a rubber spatula.
• Divide the dough into 2 pieces; place one piece between 2 lightly floured sheets of parchment paper and roll into a 1/4-inch-thick rectangle. Repeat with the other piece of dough. Refrigerate both rectangles, covered with the parchment sheets, until firm, at least 1 hour or up to several days.
• Using a 2-inch round cutter, cut the dough into 64 circles. (You can reroll the scraps once.) Place the cookies about 2 inches apart on ungreased baking sheets and chill for 20 minutes. Preheat the oven to 325 degrees.
• Bake the cookies until they are set and slightly darker around the edges, about 20 minutes. Cool completely on wire racks.
• Meanwhile, prepare the filling: Using a mixer, cream the butter and shortening until fluffy. Beat in the confectioners' sugar and vanilla.
• Flip half of the cookies upside down and top each with 1 level tablespoon of filling. Press the remaining cookies on top to make sandwiches.