From Food and Wine, Flo Braker, December 2008
2 sticks unsalted butter, softened
1/2 cup plus 1 tablespoon sugar
1 teaspoon pure vanilla extract
1/4 teaspoon salt
2 1/4 cups plus 2 tablespoons all-purpose flour
1 tablespoon finely ground espresso or strong coffee beans
4 tablespoons unsalted butter, softened
1/3 cup packed light brown sugar
1 tablespoon strong-brewed espresso or strong coffee
1 tablespoon light corn syrup
Pinch of salt
40 chocolate-covered espresso beans or Trader Joe's Espresso Pillows
Preheat the oven to 300° and position a rack in the center of the oven. Line the bottom of a 9-by-13-inch baking pan with parchment paper.
In the bowl of a standing electric mixer fitted with the paddle, beat the butter with the sugar at medium speed until fluffy and very pale, about 5 minutes. Beat in the vanilla and salt. In a small bowl, whisk the flour with the ground espresso beans. Add the dry ingredients to the mixer in 3 batches, scraping down the side of the bowl and beating just until the dough is combined.
Press the dough into the baking pan in an even layer. Spread a sheet of plastic wrap directly onto the dough and, using a flat-bottomed glass, smooth the dough into an even layer. Remove the plastic wrap and bake the shortbread for about 50 minutes, until very lightly browned on top and firm but not solid to the touch. Transfer the pan to a rack to cool slightly, about 10 minutes.
Using a ruler, cut the warm shortbread lengthwise into 8 strips, then cut crosswise into 5 rows. (I screwed this part up. This means you need to make your 8 cuts on the 9" inch side and your 5 on the 13" inch side). Let the shortbread bars cool completely.
In a small, heavy saucepan, combine the butter, brown sugar, espresso, corn syrup and salt and bring to a boil over moderate heat, swirling the pan. Boil just until slightly thickened, 1 1/2 to 2 minutes; remove from the heat. When the bubbling subsides, immediately pour the hot glaze over the shortbread. Working quickly with a small offset spatula, spread the glaze in an even layer. Using the tip of a lightly oiled paring knife, score the glaze between the cuts, without dragging. Press an espresso bean into the center of each bar. Let cool slightly, then carefully lift out the bars and transfer to a plate.
The bars can be stored in an airtight container for up to 1 week.
Yield 40 bars