Kahlua Truffle Triangles
Ingredients for the Crust:
1/4 teaspoon salt
6 ounces (12 tablespoons) cold, unsalted butter, cut into 10 pieces; more for the pan
Ingredients for the Filling:
1 pound semisweet or bittersweet chocolate, broken into squares or very coarsely chopped
3/4 cup whole milk
1/4 pound (½ cup) unsalted butter,cut into 6 pieces
2/3 cup granulated sugar
2 tablespoons Kahlua liqueur
Directions for the Crust:
In a food processor, combine the flour, confectioners' sugar, and salt. Process the ingredients briefly to combine, about 15 seconds. Scatter the cold butter pieces and the vanilla over the flour mixture and process, using short pulses, until the dough begins to form small clumps, 1 to 1-1/2 minutes. Turn the dough into the prepared pan. Using lightly floured fingertips, press the dough into the pan in a smooth even layer. Bake until pale golden, especially around the edges, 22 to 25 minutes. Do not overbake or the crust will be hard and crispy. Transfer the pan to a cooling rack and lower the oven temperature to 325 degrees.
Directions for the Filling:
In a stand mixer fitted with a paddle attachment (or in a large bowl, using a hand-held electric mixer), beat the eggs, sugar, and Kahlua on medium-high speed until foamy and lighter in color, 2 minutes. Reduce the speed to low and gradually add the chocolate mixture. Stop the mixer and scrape down the bowl and beater. Beat on medium speed until well blended, about 30 seconds.
Pour the chocolate batter over the baked crust and spread evenly. Bake until the sides are slightly puffed and a toothpick inserted near the center comes out wet and gooey but not liquid, 30 to 35 minutes. Transfer the pan to a rack. As it cools, the center may sink a bit, leaving the edges slightly (about 1/2 inch) elevated. While the filling is till warm, use your fingertips to gently press the edges down to the level of the center, if necessary. When completely cool, cover with plastic and refrigerate until very cold, at least 12 hours or up to 2 days. (You will be in a state of great anticipation. But all yummy things come to she or he who waits.)
To serve. Using the foil as handles, lift the rectangle from the pan and set it on a cutting board. Tipping the rectangle, carefully peel away the foil. Using a hot knife, cut the rectangle lengthwise into 1-1/2-inch strips, wiping the blade clean before each cut. Cut each strip on alternating diagonals to make small triangles. Let sit at room temperature for about 5 minutes fore serving.
Yields about 6 dozen 1-1/2 - 2-inch triangles.