Peanut Butter Toffee Bars
1/2 cup butter, at room temperature
1/2 cup creamy peanut butter
3/4 cup packed brown sugar
1 large egg yolk
1 1/2 cups flour
1/2 cup quick oats
1/4 teaspoon salt
3 cups dark or semisweet chocolate chips
1 cup toffee baking pieces
1. Heat the oven to 350°. Line a 9- by 13-inch baking pan with parchment paper.
2. In the large bowl of an electric mixer, beat the butter, peanut butter, sugar, and egg yolk on medium-high speed until the mixture is smooth and creamy, about 2 minutes, scraping down the sides of the bowl if necessary. Add the flour, oats, and salt and beat the mixture on low until the ingredients are just blended, about 30 seconds.
3. Press the mixture evenly into the bottom of the prepared pan. Bake the crust until it is golden brown, 15 to 20 minutes (be very careful not to overbake - I baked my for 18 minutes and they were too done; the bottom layer was a little dry, and the chocolate didn't stick well to it).
4. Remove the pan from the oven and scatter the chocolate chips evenly over the crust. Return the pan to the oven for 1 minute. Remove the pan again and, using a small offset spatula, spread the chocolate evenly over the crust.
5. Sprinkle the toffee pieces over the chocolate, gently pressing them into place.
6. Set the pan on a wire rack to cool until the chocolate has set, about 2 hours. Using the edges of the foil, lift the dessert from the pan, then cut it into rectangles.