High Country Baking: Chocolate-topped dulce de leche cookies

High altitudes make cookies spread in the pan, cakes fall, and few baked goods turn out as they do at sea level. This twice-monthly column presents recipes and tips that make baking in the mountains successful. Caramel-like dulce de leche sandwiched between two squares of crisp vanilla shortbread and top them with dark chocolate — that combination of tastes and textures is mouthwatering-good. I used them in this cookie and I'm delighted with the result. Pair them with something cool and creamy (think sorbet, ice cream or custard) and you've got a lovely dessert, include them on a cookie tray, nibble them with a coffee, or eat them as a snack. They're welcome anywhere and anytime. Chocolate-topped dulce de leche cookies Makes 14 two-inch square sandwich cookies. Make on a shiny metal cookie sheet. Active time: 35 minutes Total time: 2 hours Cookie dough 8 tablespoons unsalted butter, cut into 16 pieces, softened if making with a mixer, cold if using a food processor 2 ounces cream cheese, cut into pieces and softened 1/4 cup granulated sugar, preferably superfine 1/4 teaspoon table salt 1 teaspoon vanilla paste or extract 1 cup unbleached all-purpose flour Chocolate Topping 3 ounces semi-sweet chocolate, finely chopped 1/2 teaspoon canola oil Chopped hazelnuts, optional Filling 1/4 cup dulce de leche, room temperature Get ready: Preheat the oven to 375 degrees with a rack in the center position. Line a cookie sheet with parchment paper. Have a second cookie sheet ready to place under the parchment-lined one to provide insulation and prevent the bottom of the cookies from overbrowning while baking. Make the cookie dough: With a mixer: Beat the butter with the cream cheese until it's smooth. Add the sugar and salt and beat until the mixture is creamy. Stir in the vanilla, and then gradually add the flour, stirring only until it is no longer visible after each addition. When the dough starts to come together, stop stirring and gently knead until it is smooth and coherent. With a food processor: Put the flour, salt, and sugar in the bowl and pulse briefly to combine. Add the vanilla, cream cheese and butter and pulse until the dough starts to come together but stop before it forms a ball. Turn the dough out of the processor and gently knead until it is smooth and coherent. Pat the dough into a disk, wrap it in plastic wrap and chill until it is firm enough to roll out. Roll and cut the dough: Place the dough between two sheets of waxed paper and roll to a thickness of just over 1/8 of an inch. Remove the top sheet and, using a 2-inch square cookie cutter, cut out the cookies and place them about an inch apart on the prepared cookie sheet. Re-roll the scraps of dough and cut out more cookies. If the dough gets soft, chill it before cutting out more cookies. Place the cut-out cookies, on the parchment paper-lined cookie sheet, spacing them at least 1/2-inch apart. Chill the cookies: (This helps prevent the cookies from spreading while baking.) Lightly cover the cookies with a sheet of waxed paper (use the one you rolled them out on), place the cookie sheet in the freezer and freeze until the cookies are very firm, at least 15 minutes Bake and cool the cookies: Remove the pan from the freezer, place it on the second cookie sheet (see Get Ready above). Move both pans to the oven and bake until the tops of the cookies are set and the bottoms and sides of the cookies are golden, about 9-15 minutes, but time will vary depending how cold the cookies they go in the oven. Remove the baked cookies from the oven and immediately transfer them to a rack to cool completely. Make the topping: Melt the chopped chocolate in a microwave at a low heat, stirring after every minute of heating. Chocolate burns very easily, so remove it from the heat with some small lumps still visible and stir until all are melted. Add the canola oil and stir until the mixture is smooth and shiny, then let it cool and thicken slightly. Add the topping: Select half of the cooled cookies to use as the tops of the sandwich. Drizzle chocolate topping decoratively on them and (if using) sprinkle chopped hazelnuts over the chocolate. Refrigerate or set the cookies aside so the chocolate can firm up. Add filling and make sandwich: Stir the Dulce de Leche so it's softened and easy to spoon. Spread a little less than a half teaspoon on each of the remaining cookies. Place the chocolate-topped cookies on the filled ones and gently press down to create the sandwich. If the filling is soft, refrigerate the cookies, covered, until it firms up. Store: The cookies can be stored, well covered, for up to three days in a cool place or the refrigerator.