Imagine if your favorite peanut butter cups had an added layer of peanutty shortbread on the bottom. Well, that's exactly what these Peanut Butter and Chocolate Shortbread Bars from Fine Cooking Cookies are all about.
They begin with a buttery, crumbly shortbread studded with roughly chopped salty peanuts. Once the shortbread cools, it's spread with a layer of salty-sweet peanut butter mousse and finally topped with a glossy coating of chocolate ganache. These bars are part candy, part cookie—when cut into tiny squares, they bring to mind fun-size candy bars.
- Yield:makes 4 dozen 1 1/2-inch-square bars
- Active time: 1 hour
- Total time:3 hours
- For the peanut shortbread crust:
- 7 ounces (14 tablespoons) unsalted butter, melted and cooled to just warm
- 1/2 cup granulated sugar
- 1/2 teaspoon table salt
- 9 1/2 ounces (2 cups plus 2 tablespoons) unbleached all-purpose flour
- 1/2 cup unsalted peanuts, finely chopped
- For the peanut butter filling:
- 1 cup creamy peanut butter (not natural but an emulsified variety such as Jif)
- 3 ounces (6 tablespoons) unsalted butter, at room temperature
- 6 ounces (1 1/2 cups) confectioners’ sugar
- 1 teaspoon pure vanilla extract
- For the ganache:
- 5 ounces good-quality bittersweet chocolate, such as Lindt Excellence, chopped (about 1 heaping cup)
- 1/2 cup plus 2 tablespoons heavy cream
Make the peanut shortbread: Line a straight-sided 13x9-inch metal baking pan with foil, letting the ends create an overhanging edge for easy removal.
In a medium bowl, stir the butter, sugar, and salt. Stir in the flour and peanuts to make a stiff dough. Press the mixture evenly into the bottom of the prepared pan. Prick the dough all over with a fork. Refrigerate the pan for 30 minutes (or freeze for 5 to 7 minutes), until the dough is firm.
Meanwhile, position a rack in the center of the oven and heat the oven to 325°F.
Bake the dough for 20 minutes, then reduce the oven temperature to 300°F and bake until the crust is golden-brown all over and completely set, 20 to 25 more minutes. Let the crust cool completely before topping.
Make the peanut butter filling: Put the peanut butter and butter in the bowl of a stand mixer fitted with the paddle attachment (or in a large bowl for hand mixing) and beat on medium speed until smooth, about 1 minute. Add about half of the confectioners’ sugar to the mixer along with the vanilla and 1 Tbs. hot water. Beat on low speed until combined, then on medium speed until smooth and fluffy, about1 more minute. Beat in the remaining sugar and mix, about 1 more minute, until the mixture is smooth and thick, like frosting. If the filling seems too stiff, add another 1 Tbs. hot water and beat for another minute.
With a knife or metal offset spatula, spread the filling over the fully cooled crust. The filling may not spread smoothly and evenly, but don’t worry; the ganache will cover it.
Make the ganache: Put the chocolate in a small heatproof bowl. In a small saucepan, bring the heavy cream to a boil. Remove from the heat and pour over the chocolate. Let sit for 3 minutes. Stir gently with a rubber spatula until combined and smooth.
Spread the ganache over the peanut butter filling with a metal offset spatula to coat evenly. Let the bar sit for at least 3 hours to allow the ganache to set before cutting (or refrigerate for 1 hour).
Carefully lift the bar from the pan using the foil sides and transfer them to a cutting board. Separate the foil from the bar by sliding a spatula between them. Cut into 1 1/2-inch-square bars. They will keep at room temperature for 1 week.