Coffee gives the classic flavor combination of chocolate and toffee an unusual accent. For another change of pace, cut these layered cookies into triangles instead of rectangles.

Chocolate Toffee Bars

Crust:
3/4 cup unsalted butter, softened
3/4 cup firmly packed brown sugar
1 large egg yolk
1 1/2 cups all-purpose flour
1/4 teaspoon salt

Coffee Topping:
1 tablespoon instant espresso or coffee powder
2 teaspoons pure vanilla extract
1 (14-ounce) can sweetened condensed milk
2 tablespoons unsalted butter
6 squares (6-ounces) semi-sweet chocolate chopped
6 squares (6-ounces) white chocolate, chopped
1 cup toasted chopped pecans

1. Preheat oven to 350°F (175°C). Line a 13 x 9 x 2-inch baking pan with foil; lightly butter the foil.
2. Beat the butter and the brown sugar in a large bowl with an electric mixer set on medium speed until smooth. Add the egg yolk and beat well. Stir in the flour and salt until well mixed. Press the mixture into the bottom of the prepared pan.
3. Bake for 20 minutes or until golden brown. Set the pan on a wire rack to cool slightly.
4. To prepare the topping: Stir the instant coffee and vanilla in a large microwaveable bowl until well blended. Stir in the condensed milk and butter until well blended.
5. Bake for 12 to 15 minutes or until set. Sprinkle the surface with the chopped chocolates in a decorative pattern. Bake for 1 to 2 minutes longer or until the chocolates are melted. Sprinkle with the pecans. Cool completely on the wire rack. Refrigerate 30 minutes or until the chocolate is firm. Cut into bars or diamond shapes to serve. Store in a tightly covered container.

Makes about 24 bars.