Ingredients

The following ingredients have 4 Servings
  • 1/2 cup plus 2 tablespoons (160g) creamy peanut butter ((see headnote))
  • 1 cup (190g) packed light brown sugar
  • 1 large egg (plus 2 large egg yolks)
  • 3/4 cup (105g) all-purpose flour
  • 1 teaspoon baking soda
  • 1/2 teaspoon salt
  • 1 cup (150g) salted or candied peanuts (coarsely chopped)
  • 11 tablespoons (150g) unsalted butter (at room temperature)
  • 1 cup (85g) Dutch-process cocoa powder ((see headnote))
  • 1/2 cup (100g) granulated sugar
  • 1/2 cup (95g) packed light brown sugar
  • 1/4 teaspoon salt
  • 1 teaspoon vanilla extract
  • 2 large eggs (at room temperature)
  • 1/2 cup (70g) all-purpose flour

Instruction

  • Lightly butter a 9x13-inch (23x33cm) baking pan. Line the bottom with a sheet of parchment paper, letting it overhang the two longest sides of the pan. Preheat the oven to 350ºF (180ºC0.
  • Make the peanut butter layer by beating together the peanut butter, brown sugar, egg, and egg yolks, in a medium bowl until smooth, light, and creamy. (You can also use a stand mixer fitted with the paddle attachment.) Stir in the flour, baking soda, salt, and two-thirds of the chopped peanuts. Spread the peanut butter cookie dough in the prepared baking pan in an even layer. If using your clean hand for the task, moistening it with water or a shot of non-stick spray will help keep the dough from sticking as you pat it down.
  • Make the brownie layer by melting the butter in a small saucepan over low heat, adding the cocoa powder when the butter is mostly melted, stirring or whisking until completely smooth. Remove from heat and set aside.
  • In a large bowl, whisk together the granulated and brown sugar, salt, vanilla, and eggs until smooth and slightly pale, which'll take about 2 minutes. (You can also do this in a stand mixer fitted with the whip attachment.) Stir in the cocoa and melted butter mixture, then the flour, just until combined. Spread the brownie batter over the peanut butter layer and sprinkle with the remaining chopped peanuts.
  • Bake until the center of the brownies feel just about done, but not overbaked; a toothpick inserted into the middle will come out with moist crumbs attached, about 25 minutes. When it comes to brownies, it's usually better to err on the side of underbaked than overdone.
  • Remove from heat and let cool completely. When cool, run a knife around the short edges of the bars in the pan (that aren't enclosed by the parchment paper) then lift the bars out and cut into squares or rectangles with a sharp knife.